Dear Richard,
Thanks for this question! I have
previously discussed putter balancing in a general way, and your question prompts me to get into this important issue more deeply. This means that I need to try to clarify the relationship between putting balance schemes and how these affect the dynamics of the stroke.
But before I do, allow me to give a short answer to your precise question: Yes, "reverse face balancing" in putter designs has merit, but what you really want to know is how this compares to other sorts of balancing, so let's get cracking!
"Putter balancing" is usually spoken of as the relationship between the shaft axis and the putterhead in gravity, but this depends on how the shaft axis is oriented in gravity. The usual way is to poise the shaft axis horizontally in gravity, balancing the total putter on a point along the shaft roughly ten inches up from the putterhead where the mass below this point towards the sole equals the mass above this point towards the top of the handle. The purpose of this total-putter balancing is to remove any holding of the putter shaft in a specific orientation and allow the shaft to roll or rotate as dictated by the putterhead's weighting influenced solely by gravity.
Here is a picture of a golfer balancing several different sorts of putters with the shaft axis held horizontally:
At left is a "face balanced" putter, at right is a "heel balanced" or "toe hang" putter, and in the middle is an intermediate "45-degree hanger" made famous by the Ping putters of the 1960s and 1970s.
This illustrates face balanced and heel balanced (ignore the putterhead drawings as they are misleading):
So the three basic categories or sorts of weighting and balancing schemes are:
1. Face balancing, with the face also horizontal aimed straight to the zeneith of the sky;
2. Heel balancing, with the heel-toe axis and face aimed vertical; and
3. Toe hanging, with the face and the heel-toe axis at a tilt out of vertical or horizontal.
"Reverse" face balancing is simply "face balancing" but with the face aiming down at the center of the earth instead of up to the zenith of the sky. How's that?
The difference is in whether the shaft axis aims at the heel-toe axis of the putterhead in a way that is either the same as the putterhead center of gravity (COG), ahead of the COG more towards the target, or behind the COG more away from the target. Usually, the shaft axis meets the putterhead in front of or ahead of the putterhead COG. When this putter is balanced on the finger, the putter face is on top aiming at the sky and the heavier rear of the putterhead is underneath the shaft axis. In a "reverse" face balanced putter, the shaft axis enters the putterhead BEHIND the putterhead COG, so that balancing the shaft horizontally on the fingertip has the face swing down underneath the shaft axis and aim at the ground horizontally.
A different face-balancing scheme is to have the shaft axis enter the putter head so that it meets the putterhead COG exactly. This is called "perfect balancing." A putter with perfect balancing, when balanced on the fingertip, will STAY in whatever orientation it is placed, because there is not under-above imbalance of the putterhead COG in relation to the shaft axis.
Before we go on to "reality" balancing, let's ruminate a bit of stroke dynamics in connection with this "usual" way of talking about putter balancing (i.e., fingertip balancing of shaft in horizontal orientation).
This is from the
Alan Strand's Dandy Putter, a "reverse face balanced" putter that he described as an "Onset" hoseling (i.e., with the shaft axis meeting the putterhead behind the putterhead COG.
"Take a look at the putters you're using now. Unless it's a Dandy - it's what's called an OFFSET or "toe-throw" putter. This simply means that the shaft is in front of the putter face. Now think about it. Your goal is to hit the ball into the cup. But with an OFFSET club - the shaft or hosel obscures full view of the putter face.Ź
In other words - you're basically swinging blind.Ź
Not So With The Dandy!
The Dandy has a totally new design - called ONSET. The shaft is behind the face - giving you a clear view of the putter face and the ball - all at the same time. So when you stroke - you actually see the face moving towards the ball. No guesswork involved.??In fact - the Dandy incorporates a unique alignment design right on the putter itself! You'll see exactly where the ball will be hit - each and every time. It virtually takes the "Kentucky Windage" out of your putting game.
That's Not All
Just giving you a clearer view of the putt would be good. But not good enough for us! The Dandy was constructed from the bottom up - trouncing the performance of every other putter on the market today.
IMMEDIATE ROLL
Dandy's exclusive ONSET design gives you a huge benefit - immediate roll. Upon impact - the ball is actually lifted with overspin - in what's called "dynamic lofting." Now what's so important about this? The sooner your ball starts rolling - the straighter it goes - and the less likely it'll get knocked off line. Meaning your putts will be much more consistent. Greater consistency - more putts will drop. And so will your scores. It's that simple. Ź
With OFFSET putters - just the opposite happens. The ball actually backspins, forcing you to reverse the problem by manipulating the putter. Not an easy attempt for us mere mortals. That's why we say - It's better to be ON than OFF. Onset that is.Ź
The Dandy putter is the first Onset Face Balanced putter (putter face pointing towards the ground) that delivers its full force at impact. It resists twisting throughout the entire back-swing and follow-through. ItÕs like the little red wagon analogy? ItÕs easier to pull the wagon by the handle than to push it by the handle. The same thing applies to putting! ItÕs easier to pull the mass (putter head) backwards, than it is to push the mass backwards. Once we get the putter to the top of our backstroke, we gain gravity as an ally. With gravity on our side, the Dandy putter wants to work the line and swing down without manipulation through impact, where it matters most."
This is from
Alex Gamill's Railgun Putter, a "perfect" balanced putter with the shaft axis meeting the putterhead COG:
"Even "face balanced" putters want to twist in your hands. The putter's weight must be distributed evenly, forward to back, and heel to toe.Ź The RailgunTM has perfect symmetry for perfect balance."
This is from
Peter O'Leary's Drop Putter from Australia, an example of so-called "reality balancing":
"The Reality Putter
Face Balancing" a Golfing Myth?
I have been a putter designer and manufacturer for 18 years. During that time I have seen many weird and wonderful types of flat sticks, I've also managed to produce a few strange ones myself. In my search for justice on the greens I have designed and made many tools for testing the effectiveness of my putters and to measure them against those of other manufacturers.
I've always thought, "face balanced" putters were more of a conjuring trick than a genuine attempt to make a better putter. I must confess that I have made them on request from time to time but I couldn't shake the feeling that it was all just smoke and mirrors. As the demand for face-balanced putters grew I decided to investigate the phenomenon a lot more closely.
"Face balancing", as we know it occurs when you balance the shaft horizontally and the face of the putter points skyward and is parallel to the ground. This is achieved by having all or most of the head weight evenly distributed behind the shafts pivotal point.
This type of balancing would be OK if you putted with the shaft in a horizontal position. Most of us putt about 70” upright from the horizontal. If you move a "face balanced putter" from the horizontal plane just a little towards the 70” the face of the putter wants to twist open, go all the way and it will be pointing directly away from you. This twisting effect can be quite forceful with some putters.
My testing was done with some fairly sophisticated equipment but here is a simple way you can do your own testing. Push a golf tee into the hole at the butt end of the grip. Leave enough of the tee out of the hole so you can hold it loosely between thumb and forefinger. Holding the tee as described let the putter hang in a vertical position. With your other hand push the shaft away from you towards the normal swing plane angle of about 70”. The pushing action is done best with a smooth surfaced object such as a pen as there is less friction than with a finger or hand. What happens next is quite amazing you will feel the tee twisting between your thumb and finger and you will see the face of the putter twist open.
Testing your putter for Reality Balance.
When held vertically the face of the putter remains stable.
Pushing the putter out into the normal swing plane the head becomes unstable and will twist open and away from the target line.
Without knowing it all of you golfers with face balanced putters have been compensating for this movement in the head of the putter, mostly with the hands. Problem? You bet there is. Any relaxing of the normal grip pressure however slight will result in the face of the putter twisting open ever so slightly resulting the infamous pushed putt. Over compensation with the grip pressure will result in you pulling the putt. Maintaining exactly the same grip pressure during the stroke therefore becomes a critical factor in your success on the greens.
What makes it even more critical is most of us set up and start the putting stroke with the head resting on the ground behind the ball. Contact with the ground stops any twisting effect; we call this position neutral. When we lift the head up and away from the ball the twisting of the head has even greater impact on a relaxed grip that is also starting from a neutral position.
So now you have received the bad news about "face balanced" putters what about all the others. Blade, Heel & Toe Weighted and Centre Shafted. Its all bad news I'm afraid.
Blade putters are heavily weighted towards the toe. Our robotic testing concluded the same effect of "face balanced putters" only worse. If the face was closed a little then that is the way it turned, open slightly and the face wanted to open all the way. It was a bit like trying to balance a golf ball on a pinhead.
The result with Heel & Toe Weighted putters (45” hanger) also wanted to fall open.
Centre Shafted putters are mostly weight towards the toe and the results were the same as with a Blade putter.
Being a putter manufacturer I decided to do something about this phenomenon and make a putter that will remain stable when balanced freely in, and when swung through the plane of the putting stroke. I have called it "REALITY BALANCED"Ŗ.
What the "Reality Balanced" putter offers is a chance to start and finish the stroke with the head of the putter in a totally neutral position. There is no chance of the head of the putter suddenly becoming active and wanting to twist open. Maintaining the exact same compensating grip pressure each time is not necessary. It gives a golfer a great sense of wellbeing knowing that there are no outside forces at play during the stroke. In fact the "Reality Balanced" putter will enable the golfer to lighten their grip to the extreme without loosing control."
This discussion of a different way to test the shaft-butterhead balancing leads us away from holding the putter shaft horizontally towards testing the balance when the putter is held in the same orientation it has during a stroke (i.e., on an angle out of vertical matching the lie angle of the putter design).
Here is a Quick-Time movie by
David Bernhardt of Positive Putters in Indianapolis showing the difference in stroke dynamics of putter balancing schemes when the putter is held in the same orientation it has in a stroke:
MOVIE.
So there is a heel-toe balancing AND a front-back balancing in how the shaft axis enters the putterhead in relation to the putterhead COG. This is shown in these photos of the above putters:
Yes! C-Groove Amy Putter with shaft axis BEHIND putterhead COG:
Drop Putter: "A unique balancing system places 80% of the total head weight
forward of the shaft in the face of the putter, precisely along the striking zone."
Dandy Putter with shaft axis "onset" behind putterhead COG:
Railgun Putter with shaft axis centered on putterhead COG:
So far, the taxonomy shows
1. shaft axis aimed to the center of the heel-toe axis of the putterhead, either in front of or behind or centered on the putterhead COG in the front-back axis of the putterhead; and
2. shaft axis aimed off-center of the heel-toe axis of the putterhead to the heel side of center, either in front of or behind or centered on the putterhead COG in the front-back axis of the putterhead; and
3. shaft axis aimed off-center of the heel-toe axis of the putterhead almost completely in the heel, either in front of or behind or centered on the putterhead COG in the front-back axis of the putterhead.
This leaves aiming the shaft axis into the head off-center towards the toe of the heel-toe axis of the putterhead. That is the Positive Putter:
If you extend the line of the shaft axis before the bend in the hosel, the shaft axis meets the putterhead on the toe side of the heel-toe axis. This has the effect of locating the putterhead COG CLOSER TO THE GOLFER than the point where the shaft axis enters the putterhead. A couple of other putters use this scheme --
The
Axiss Putter: "The Axiss Putter features a reverse angled head that brings the head of the putter back toward the golfer and directly in line with the shaft."
And the
Inseyed Putter: "The putter head is inside or closer to you thus moving its center of gravity closer to the user, thereby making it easier to stroke it in a pendulum motion."
The only other dimension to consider in the shaft axis relation to the putterhead COG is up-down. But strictly speaking the shaft axis is an imaginary line that extends to infinity thru the putterhead, so the shaft axis has no up-down dimensionality. Even so, the shapes of hosels dispose the mass of something related to the shaft above the putterhead COG, so in this sense there is something to take into account. It sort of depends on whether you consider the hosel as part of the shaft or part of the putterhead. But in any event, if the "putterhead" has a COG and this COG is altered by the mass and shape and positioning of the hosel, then the hosel is a factor in the putter balancing, as it affects the balancing in all three dimensions.
Consider this Ping "offset" hosel:
The shaft axis aims at a point short of the heel-toe center towards the heel (and this makes the putter a 45-degree hanger), but the shaft angle aims in front of the putterhead, so this makes it a "sky up" sort of putter with most of the weigth of the putterhead in the back sinking underneath the shaft as balanced horizontally. The fact that the offset hosel adds some weight ABOVE the otherwise front-back and left-right symmetrical putterhead means that the putterhead-plus-hosel object has a COG that is not exactly where it would be in a straight-in hosel. If you tried to balance this putterhead on the center of the heel-toe axis on an extended right index finger, the hosel would tip the putterhead heel-down. The hosel would also tip the putterhead so the plane of the face tilts towards the arms and face of the person doing the balancing. This latter is the up-down effect of the hosel being assymetrical to the putterhead's up-down balance or symmetry.
To locate the putterhead-plus-hosel COG, the golfer simply spins the shaft between his hands, like a Native American using a bow to spin a stick set in a twist of the string to rotate the point on a plank to make a fire. Or, like a person making a "snake" by rolling playdough in between his two palms. The point of the putterhead that is the stationary center of the head as it spins back and forth at the end of the shaft is the COG identified in the heel-toe and front-back or left-right dimensions, but this does not directly reveal the COG in the up-down dimension even though the up-down location is having its effect.
This
article by Scotty Cameron discusses what he calls "the neck" of the putter:
"In the Art of Putter making, there is one major factor that influences performance and design. That is the neck of the putter. It is such a simple component that attaches the head of the putter to the shaft but the effects it can have on the look, feel and playability are immense. I make many different types of necks but letÕs talk about necks in relation to the design of the putter at a standard lie of 71 degrees. The reason I mention this final point is because an extreme lie angle can affect toe flow so for the sake of this article, we will be talking about standard lie with a tolerance of 2 degrees (flat or upright).
I will break it down into three categories; full hang, quarter hang, and face balanced. I will break down each category further but first letÕs understand more about the neck.
The height of the neck is one of the components that sets toe flow. Typically, a shorter neck equates to more toe flow and a longer neck means less toe flow. Think of a long neck Scottydale and Santa Fe. The longer neck changes the shaft axis more to the center of the topline which creates less toe flow and more face balance in a design.
Offset also contributes to toe hang. The normal offset on a putter is one shaft diameter offset from the topline of the face. More or less offset and I can manipulate the toe flow of the design. If offset is reversed to onset, it also reverses the balance of the putter. When I make a putter, I want the neck to look like it belongs there, whether I am making a mechanical design like the Newport, or a softer natural design like a Studio Design 1. In the Studio line this year, I mixed natural designs with more mechanical necks. I have been doing that on Tour for years with excellent feedback and it was received with great success in the market. Not only should the neck look like it belongs there, but at setup I like the image that if I poured water on the putter what would the neck look like if it grew out of the head. I build many prototypes before I come to this point even though it looks so simple. In fact, we have changed the neck on the Newport several times since its inception. One of the biggest changes was making a flat front plumbing neck. The older model had the socket or barrel of the hosel positioned in the middle of the neck. In the new design, we push the socket back slightly making the front of the hosel and the socket flush so there is no distortion. Many players who used plumbing neck style designs and always had a problem with the neck looking crooked, skewed and not square to the topline. I didnÕt invent the plumbing neck design, but certainly refined it to better fit the eye of players. Many guys, including the top players in the world use a putter with a flat front design.
Now letÕs talk about how the hang of the toe of the putter contributes to performance.
Full Hang
This type of putter creates natural, extreme toe opening during the back swing, and closing at follow through. It can be a difficult putter to use depending on ball position and timing. Other examples of full toe hang putters are the Del Mar 3.5, Scottymaster, JAT and several of the Studio Design models. In these designs, I start with the hosel at the far end of the heel. They are traditionally short necks and like the 3.5 have one shaft diameter offset. The necks can be round, flat sided, or any combination, but when they are short and located at the heel of the putter with a standard offset, I will achieve full toe hang. The full toe hang putter is for guys who have great timing and need the putter to open during the backswing, which keeps the putter from going outside.
Quarter Hang
The quarter toe hang putter in my opinion is set with optimal performance in mind, and isnÕt extreme when it comes to path. The quarter toe hang putter slightly opens during the back stroke, and slightly closes at the follow through. This design is great for the player who needs a little toe flow while retaining the ease of use this design provides. Examples of putters with this type of neck design are the Newport, Newport 2, Mid-Slantnecks, Laguna, Coronado, etc. As you can see from the different models I can make a quarter toe hang design with mechanical or plumbing style neck or a natural, round flowing neck. The traditional quarter toe hang putter is the Newport, but I had guys on Tour who told me the hosel and socket position got in the way of the ball. So I started experimenting with the slantneck design, which I really like. I started by removing the elbow where the hosel and socket connected, and welded the socket to the top of the neck with no offset. I created offset by moving the hosel forward or slanting it one shaft diameter forward of the face and keeping the socket in the same position. The result was a cleaner transition from the socket to the hosel, better visibility of the ball at address, all the while retaining the quarter toe hang that I was looking for. Next time you pick up a slantneck take a look and see what I am talking about.
Face Balanced
A face balanced putter is one where the axis of the shaft crosses the center of the putter head. So in order to create a neck that does this, I need to go up or move the hosel closer to the center. Examples of face balanced putters with this type of neck are of course longnecks, long slantnecks, and center shafts where there is a short hosel. The face balanced putter is more for the player who takes the putter straight back and straight through. I donÕt do a lot of face balanced putters because I believe a putter needs a little toe flow to get to the inside and close properly at follow through. There are guys who are very good at taking the putter straight back and through and a face balanced putter better fits their stroke. The long neck allows me to get the proper shaft axis with standard offset, standard lie, and without manipulating the shaft.
Speaking of manipulating the shaftÉ..We have only been talking about those designs with necks, but I do several different designs with no necks at all and the new Futura is one of them. You may be saying to yourself that I was just saying that quarter toe hang is optimal and now he is talking about the Futura, which is face balanced. The Futura is a face balanced design but I achieve face balance by gravity and not shaft axis. The shaft axis of the putter is short of center and would perform like a quarter toe hang design but it is the heavy stainless horseshoe in the back that creates the face balance. So in fact the Futura is a ? hang design with gravity creating the face balance. Give the Futura a try and you will feel the toe flow even though the face points to the sky. I also do the center shaft design which positions the hosel just back of center so I get very little toe hang. The new designs in the Studio collection are the Studio Design 5 and 6. The 5 has a low bend and like a short neck gives me the ? toe hang I am looking for because the bore angle of the shaft complements the shaft bend. The Studio 6 has a high bend, like a long neck, moving the shaft axis to the center of the putter head giving it face balance.
Next time you pick up your putter take a look at the neck, or lack thereof, and see how the design affects performance. A lot of work went into making that neck so I hope this article helps you better understand your putter design. Here are pictures of different necks so you can see what I am talking about."
In Scotty-speak, the term "neck" is used thusly:
Face Balanced Š When the shaft of the putter is balanced on the finger the face points upwards towards the sky achieving less toe flow. See Toe Flow
Flowing Neck Š A flowing neck is achieved when the curve of the neck flows from a long, round neck. The shorter the neck the more kink or angle in the bend and less flow. The flowing neck adds offset to the putter and gives different appearance at address.
Lie Š Angle of neck from a horizontal sole . Angle is flat as it lays back and upright if it lays up.
Plumbers Neck Š Scotty was under his sink fixing a leak and the bends in the pipes were reminiscent of the neck on one of his putters. The term plumbers neck was born and describes the neck of the Newport or Classic 1 which was in turn used on several other models.
Slant Neck Š Scotty wanted to get rid of the elbow of the plumbers neck for a sleeker more unobstructed look at the ball, but retaining the ? hang of the plumbers neck. The slant neck gives a cleaner look at the ball.
Swan Neck Š Hot bend around neck to make the putter more face balanced with less toe flow. The neck has an S shape or swan neck to it when complete.
Toe Flow - The amount the putter head closes at impact due to the position of the hosel and balance. e.g., A blade style putter such as the Napa has a lot of toe flow because it is heel shafted. Conversely, a Newport style putter has less toe flow due to its plumbing neck.
SUMMING UP
The shaft-putterhead relationship is a matter of three dimensions in the aim of the shaft axis with reference to the center of gravity of the putterhead. The imaginary line of the shaft axis meets the putterhead
1. either in line with the COG along the near-far or heel-toe axis of the putterhead or more heelward or toeward of the COG in some degree; and
2. meets the putterhead either in line with the COG along the left-right or front-back axis of the putterhead or more ahead or behind the COG in some degree.
This relationship can become further complicated by the shape, position and mass properties of the hosel, as this alters the putterhead-plus-hosel mass distribution and the location of the putterhead COG in all three dimensions: near-far or heel-toe, left-right or front-back, and up-down in the putterhead.
Because the putter is not oriented horizontally when used in the stroke, the only true test of the effect of the weighting and balancing scheme of a putter is its effect on the stroke when YOU hold it. A putter with a lie of 71 degrees (usually thought of as standard) will not present the same balance when held at 72 degrees or 70 degrees. The Scotty Cameron "Detour" putter has a balancing that ONLY FITS 71 DEGREES. To get a properly balanced Scotty cameron Detour putter, you would have to have him reshape the neck to fit your setup and lie, the way he does for Tour pros. otherwise, it's not the properly balanced putter for you, and its stroke dynamics are doing things to your stroke that are not directly in your control until you subconsciously change your stroke to accommodate the odd dynamics. testing the putter's balance in your setup and lie is the key to how the putter's balancing will affect the stroke dynamics.
To a certain extent, the human brain considers everything at the end of the shaft sort of in a blur. This is a unified swinging of the business-end of the tool. This means the golfer can overcome modest putter balance influences with a voluntary controlling of the shape and character of the downstroke. The more the golfer wants the tool to swing from the top of the backstroke down and thru by itself, without human intervention or with only minimal human controls, the more putter balancing emerges as an influence.
Putter balancing that does not promote a square presentation of the putter face thru impact without human controls is a design that will require the golfer to adapt to the putter's dynamic characteristics. The putter design will influence the stroke dynamics. But if the putter balance keeps the putter face presentation square while the human exerts no control other than maintaining static relationships between body parts, then the balancing is not adding or detracting, as there is no "toe flow" in Scotty-speak. A little "toe flow" can result either in the golfer overriding the toe flow with MORE control or in allowing the toe flow to change the stroke dynamic. Which one of these is better for rolling the ball where the putter face aims at address depends on a lot of other factors than simply the design of the putter (e.g., setup, alignment, handsiness versus shoulder stroke, poor eye positioning, etc.). What Scotty Cameron is doing for Tour pros is taking stock of their stroke dynamics, seeing which way the dynamic needs tweaking (open or closed at impact), and then LEAVES THE STROKE ALONE SO THE GOLFER CHANGES NOTHING and tweaks the stroke dynamics in the balancing of the putterhead-neck-shaft relation. This
report of working with Adam Scott is typical:
"Adam Scott, a New Zealand native, was in the Putter Studio recently working with Scotty on camera to refine his putting stroke. In order for a putter to perform optimally a player needs to have a repeatable address to get into the same position each time at setup. Many guys come and work with Scotty for this very reason and Adam wanted to ensure consistency as well. Consistency means getting the shaft at 90” and the face square so it can return to that same position at impact allowing the putter to perform the way it was made to, and for the loft of the putter to do its job. Once Adam got on camera he was able to see his address and get a feel for that consistent setup. He was also able to see where the putter goes on both takeaway and follow through and how each affects performance. Scotty likes to see the putter move slightly inside on a 25Ó putt, return on path square to the target line, and finish slightly inside at the end of the follow through. Adam, a longtime Cameron loyalist has a Newport 2 GSS in his bag with a Newport 2 SSS as a backup. Scotty wanted to see the putter moving slightly more inside and made Adam a Newport 2.5 that has more toe flow than the Newport 2. He wanted Adam to practice with the 2.5 so he could feel and trust the release as the putter moves slightly inside on the follow through."
The effectiveness of these tweakings depends A LOT on the player not exerting overriding control on the design effect. So the player is being told to adapt to the tweaking by NOT controlling its effect out of existence. This is an approach that depends critically on the golfer's sensitivity and stability of stroke dynamics. If the golfer has too little sensitivity, the tweaking won't matter and the golfer will simply over-control the effect. If the golfer's stroke dynamics are not stable and consistent, the tweaking effect will get lost in the confusion.
You should also note that Scotty Cameron does not explicitly report why he felt Adam Scott's stroke needed more toe flow. Was Adam missing to the outside with an open face thru impact, and Scotty trying to FORCE Adam to get the toe more closed by designing in miore opening of the toe? Or was Adam pulling his putts, and Scotty wanted to add more toe flow and have Adam leave the extra toe flow alone and use his normal stroke dynamics to get his putts rolling more online? I have no information that shows me Scotty Cameron really has a plan for deciding which golfers with what sort of stroke dynamics needs more or less toe flow, so I'm sceptical about this process of adjustment of stroke dynamics by design.
So all putter balancing is a matter of the magnitude of the effect fitting into the golfer's sensitivity and stability of dynamics. Consider a "good" Tour pro and a "bad" amateur. Only a BIG effect will matter much to a "bad" golfer, whereas a "good" golfer would want the tweaking to come in prettty small doses.
I don't really doubt that center-shafted face-balanced putters, including reverse face-balanced putters, are not completely free of effects that tend to open the putter face in the backstroke. But between these two -- up-pointing face balancing and down-pointing face balancing -- the difference shows up in how the shaft axis affects the takeaway or the thrustroke. A reverse face balanced or "onset" putter has more effect in avoiding the toe opening in the takeaway or backstroke, because here the golfer is "pulling the cart" of the putterhead center of mass back away from the ball instead of "pushing the cart." For the forward stroke, the offset putter has the "pulling the cart" effect. For the center-set putter like the Railgun, there is no difference either way, as the golfer can be said to be "pulling" the cart back or down and thru.
In my style, I teach that the golfer wants to minimize voluntary muscle control in the down-and-thru stroke -- for two separate reasons. First, the timing will be much more consistent when reliant solely upon gravity, and this allows instinctive touch AND better accuracy of impact, as gravity "effortless" timing is always the same, whereas human effort-based timing is not. Second, I teach that the biomechanics of shoulder alignment will result in a natural resquaring of the putterface at the bottom of the stroke without human intevention, AND that the shoulderframe alignment thereafter by itself guides the stroke online, again without human intervention. (An inside-curving backstroke that is energetically modest will NOT produce an in-to-out push stroke so long as the shoulder frame does not get dragged out of square alignment by the backstroke, and instead, if the alignment remains sqaure, a gravity-sponsored "effortless" downstroke will see the putter curve in to out until it reaches the bottom of the stroke and THEN the forward momentum is guided by the body tissue and structural components of the shoulder frame -- i.e., up and down the line square past the bottom of the stroke.) Both of these teachings translate into the advice that the golfer needs to "let" the thrustroke occur from the top of the backstroke as and however it will in gravity, managing only the shoulder alignment and the pivot stability, with no independent contribution in the movement from arms, elbows, wrists, or hands. In this case, the forward momemntum of the arms and hands and putter as guided on line by the shoulder alignment and as required to rise past the bottom of the arc by the stability of the pivot will conspire to "send" the lead shoulder upward in plane -- that is, the lead shoulder will get "sent" vertically upward from the surface, and the shoulder will not "pull" back out of this plane. There is no specific "release" of the putter in an inside gating as Scotty Cameron likes to see, and timing is reduced or eliminated as a concern simply by "letting" the momentum of the stroke go where it wants beneath a stable pivot.
Presumably, an offset putter in the backstroke promotes the toe opening going back from the ball, but does not promote a reciprocating closing of the toe coming forward. That's the Ping formula, and most Scotty Cameron designs are basically Ping putters slightly modified. Golfers using Ping putters or Scotty Cameron Ping-like putters usually adapt to the effects of the putter. Karsten Solheim deliberately wanted this adaptation for the greens of the 1960s, which basically required POWER similar to the power in a chipping action to get the ball across the rough surface. Opening the toe and leaving it open by virtue of the puter design and balancing FORCED the players to learn that unless they wanted putts to go to the outside all the time, they would have to OVERCOME the design and intentionally CLOSE the putterface thru impact.
By the same token an onset putter would reduce toe opening in the backstroke, and would promote the golfer staying out of the thrustroke in favor of the putter balancing affecting the stroke dynamics in a good way. The Dandy Putter and The Yes! Amy and the Drop Putter would fall in this category.
That leaves the Positive Putter, the Axiss, and the Inseyed Putter, with the putterhead COG closer to the golfer than the shaft insert point on the heel-toe axis of the putterhead. Perhaps a modest degree of toe-ward hoseling with some onset would be a good plan? These putters would also promote leaving the downstroke up to gravity rather than to voluntary human effort.
I don't think I can get too much further down this road without a lot of testing, but I hope this helps anyway.
Cheers!
Geoff Mangum
Putting Coach and Theorist
PuttingZone.com
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