Geoff:

After reading and participating on your fine forum, I am coming to the conclusion that putting is a Best Guess Effort activity.

All the many picayune factors being discussed may be insignificant to the final result ... because once somewhat imperfect impact is completed the vagaries of the grass and ground take over and affect the skidding, hopping, rolling ball ... as it attempts to seek out the hole.

I appreciate your gestalt approach because you seem to be telling people that a decent stroke is all that is attainable and a perfect stroke is only by chance. At least that's my impression..... oh and then there is the particular anatomy and peculiar mentality of each golfer that characterizes their putting posture and stroke mechanics. The combinations and permutations become mindboggling ... !!!

The final nail in the coffin of all the marketing hype about putters and putting gizmos is the simple geometry of the angular tolerance or intolerance of the distance to the hole and the tangent trig of the 4 1/4" diameter hole .... making the hole tolerance +/- 2 1/8" ... and assuming an accommodating terminal velocity the +/- angular tolerances are:

Putt Length .. +/- Tolerance

3' ........................ 3.4º
5' .......................... 2º
10' ........................ 1º
15' ....................... 40'
20' ....................... 30'

Putting putting in this perspective should give us pause and perhaps a prayer is more appropriate than technology and science ... and as we all know ... theory is not truth ... only a best guess based on current knowledge ... and 4 million putts becomes self-fulfilling ... ??!!!

Humbly yours .... sammy

Dear Sammy,

Your doubts are pretty vague. The sceptical doubtings that you give voice to are of course legitimate starting points for exploration, but you simply cannot stop there with a firm conviction that the reasonableness of your doubts fatally indicts someone else's (e.g., my) specific and detailed explorations of reality. You have to explore your doubts yourself and find out. So do that, will you?

To invalidate a theory, you have to produce carefully derived evidence that irredeemably contradicts the theory. My "theory", such as it is, is that an understanding of the physics of the situation facing a golfer on a green (the interactions of the green, ball, and putter as weilded by the golfer), combined with an understanding of the processes of the human brain and body and the capacities of the golfer to respond effectively to the situation, counsels the golfer to seek the most effective and accurate and repeating movement strategies for putting. Whether these strategies suffice to totally control all variables has never been my thought, as this seems nonsense on the face of things. Your doubt that this could be the case is noted and agreed with, but hardly undercuts my efforts.

I don't like making statements like this, but your persistence leaves me little choice. Your imagination of the forces involved in the pattern of movement I describe seems to be uneducated by extensive and detailed experience. The simple answer is always the same: talk to me after you give it a fair trial on the green.

I like to hear more of what your personal experiences reveal, including how you interpret those experiences. Then we can talk details. I've been paying a lot of concentrated attention to what happens in putting (without a lot of self-delusion), and I certainly am ready to discuss it with anyone anywhere. But it seems pointless for me to respond to vague doubts when those doubts must in the event be addressed with experienced facts. You have to try things out and then talk honestly about the experience. Just look at the facts first.

Later,

Geoff Mangum
Putting Coach and Theorist
PuttingZone
http://puttingzone.com
Golf's most advanced putting instruction -- you're either in the PuttingZone, or not.

Fair enough Geoff ..... I ... respect your theories but you haven't been able to convince me that there is a significant gravity-sponsored pendular swing in the putting stroke, particularily for shorter backstrokes (3" - 8") and virtually no significant drop in putter elevation. My contention is that what you feel as gravity-forced is actually the angular momentum imparted to the putter by applied downstroke torque and/or force at the beginning of the stroke. If there is some gravity force acting on the elevated putter, it is too small to be humanly felt.

The advise to "keep accelerating" the putter through impact is just to ensure that there is no decelerative force to slow down the putter before it has reached it's downward nadir and begins it's miniscule upward path to impact. In fact it may be nothing more than maintaining constant velocity before impact is reached making it feel like "going over the falls in a barrel". Besides, the stroke distances are too small and temporally short for a true pendulum.

My further suspicions are that your actual putting radius is much greater than the 54" you measured from your stroke center to the putter head. It is very easy for the hands to drift back and then be forced forward to accomodate the concept of a pendulum stroke .... but by moving the hands along with the putter and thus departing from pure pendulum mechanics, it will create a much longer stroke radius ... and that explains why the elevation of the putter head can be much less than the calculated 1.35" for a 12" stroke.

This would explain why a straight back and forth putting stroke hardly rises and falls ... cancelling out gravity for pendular motion ... and thus making the straight putting stroke a shoulder torqued and hand forced stroke ... all because of minute arm and wrist articulations. (If the putter is rotated with only hand force couples and the arms are still then there will be a fixed radius and the approx length of the putter.) Moving the torso, shoulders, arms, hands do not guarantee a swing radius located in the upper torso no matter how you come to that nebulous conclusion. The center can move to well above the body depending how much the hands move linearly with the putter.

Therefore it is my contention that the straight back and forth putting stroke is not a pendular stroke ... it's a hand-arm-shoulder virtually linear-forced movement ... gravity only defines the weight of the putter and not the movement of the putter as a pendulum. In fact the cantilevered structure of the arms and putter imposes forces in the para-sagittal plane thus defeating pendular concept since the cantilevered forces are somewhat constant when holding the putter on it's shaft plane. This is my theory, based on my personal analysis of putting stroke vectors.

Your turn .... regards.

It is obvious that you have never seen a mechanical devise that has a pendulum motion with a putter attached.
I will assure you that seeing one being used, you would not be able to dispute the fact that this divise has no musles. As with a child in a swing, the parent pulls the child and swing back and the swing and child returns to the starting point and swings beyound by means of gravity. A pendulum stroke as Geoff discribes, works in the same manner.

Dear Sammy,

In trying to understand our communication gap, it strikes me that perhaps the underlying notions of the "drop" and what you describe as "feel" don't agree with my understanding. Let me try to attack the issue that way.

DROP

The "drop" of an object in gravity vertically down over a specific distance will a) take place in one and only one time span determined solely by the distance of the drop, and 2) will reach the end of the span with one and only one peak velocity also determined solely by the distance of the drop.

The "drop" or "swing" in gravity of an object (bob) at the end of a pendulum (rod fixed to a pivot) that starts at a specific height above the bottom of the swing arc (the same height as in the previous vertical-drop example) is not a drop vertically down that height span but is a combination of down and across laterally or translationally beneath the pivot. At the instant of the beginning of the drop, the direction of the object's drop is ALL vertical, but instantaneously is constrained by the pivot and rod so that the vertical dropping is transformed in a smooth manner to more and more horizontal or lateral motion. There is a blend of vertical and horizontal dropping. Starting the bob back 90 degrees off vertical so the rod parallels the ground, the bob starts 100% vertically dropping and instantly after the start of the drop, the bob is dropping (say) 99% vertically and 1% horizontally. The further along the pendular arc the bob drops back towards the bottom of the stroke, the more the bob's drop becomes horizontal and the less the blend is vertical. Right at the bottom of the arc, ALL of the bob's motion is 100% horizontal and there is no further dropping vertically allowed. Then the bob continues upward, reversing the pattern or blend of "up" and "across" with increasing "up" and decreasing "across".

The interesting thing about the HEIGHT of the drop of a pendulum is that the TIME required for the bob to reach the bottom along a lengthy pendular arc is the NOT THE SAME as the time of a vertical drop from tghe same height, but the peak speed at the bottom of the pendular swing is the SAME as the PEAK SPEED after a vertical drop from the same height. The "peak speed" is really horizontal velocity in a pendulum, whereas in a vertical drop the "peak speed" is vertical velocity. Hence, the pendulum transforms the gravitational acceleration of a vertcal drop to the SAME velocity horizontally as the bob would have by dropping vertically.

Let me show that the two calculations are the same peak speed.

Vertical drop: 1.35 inches of vertical drop (H) in gravity (g = 384 inches / second per second acceleration on earth) results in a drop that takes TIME T = SQR(2 x H / g) and that reaches a peak vertical velocity (PVV) at the end of the drop of PVV = T x g. Starting with H = 1.35 inches,

T = SQR(2 x 1.35 / 384) = 0.0834 seconds

and peak velocity at end of 0.0834 seconds of gravtitational acceleration is

PVV = 0.0834 x 384 = 32.2 inches per second vertical velocity.

Pendular swing: 1.35 inches starting height with a rod 54 inches long (L) and a backstroke 12" back from vertical results in a drop that takes TIME T = 2 pi SQR(L / g) = 2 x 3.14 x SQR (54 / 384) = 2.35 seconds from top of backstroke to top of thrustroke and back again to top of backstroke. We're only interested in the time from top of backstroke to bottom of swing arc, which is 1/4th this time, or 0.59 seconds. The pendulum transformation of a 1.35" drop eventuates into a swing of 12"+ along a circular arc that requires a lot more time to traverse, 0.59 seconds, whereas the vertical drop rerquires only 0.083 seconds (12 times longer motion).

The peak horizontal velocity (PHV) of the bob (putterhead) at the bottom of the swing arc starting at maximum angle off vertical of THETA degrees (12.84 degrees to raise putter 1.35") is just the same as the PVV, from the formula

PHV = SQR(2 x g x [Lx(1-cosTHETA)])
PHV = SQR(2 x 384 x 54 x [1 - cos(12.84 degrees)])
PHV = SQR(2 x 384 x 54 x [1 - 0.975])
PHV = SQR(2 x 384 x 54 x 0.025
PHV = SQR(1036.8)
PHV = 32.2 inches per second of horizontal velocity.

That's interesting! For the starting height of 1.35", the pendular swing of a 54-inch length rod has the bob (putter head) moving down and across in a period of time 12 times longer to arrive at the SAME peak velocity as a vertical drop of the same height. All of the potential energy of the height becomes transformed by the pendulum arrangement into horizontal velocity at the bottom of the stroke that is exactly the same velocity as gravity gives a vertical drop from the same height.

The longer the pendulum, the slower the putter head accelerates smoothly along a longer arc from its starting height to the SAME peak velocity it would get in a much shorter and faster vertical drop.

No torquing is required to generate this 32.2 inches per second velocity at the bottom of the pendular swing. Gravity does it all.

FEEL

"Feeling" the difference between a gravity vertical drop and a pendular swing from the same height is not the same, although the forces involved at impact are the same.

In a gravity free-fall vertically of the hand onto the thigh from 1.35" height, the only "feel" is the impact of stationary thigh against underside of hand. If you raise the hand 1.35" and really relax and "drop" it, you feel a "pat" against the thigh. You can see about the same thing by lifting a golf ball one diameter high (1.68" -- not too much higher) and dropping it onto your open palm. Now if you took a 360 gram putter head and lifted it 1.35" off the palm and thenm dropped it, you would "feel" the same energy ("momentum", mass times velocity at impact) that the ball would "feel" in a pendular swing from the same height (i.e., 12" backstroke raising the putter head 1.35" off the ground). This "force" will generate a ball speed off the putter face of 1.56 times the putter head speed at impact, or 50.2 inches per second. On a Stimp 10 green where a ball exits the Stimpmeter at about 70 inches per second to roll 10 feet, the 50.2 inches per second ball will roll about 5/7th of 10 feet, or 7.2 feet (10' * 50/70).

I don't know that a human hand weighs as much as a 360 gram putter head, so the analogy of dropping the hand onto the thigh may not quite be enough force to compare. Dropping a 360 gram putter head onto the palm or thigh, though, would do the trick.

In comparison, the "feel" in a pendular swing is more complex and involves more body parts and areas DURING the down-fall over a much LONGER period of time, and thereafter the "feel" of impact is added to the experience. While it may be true that the v elocity at impact is the same in both cases, and so the momentum or energy transferred into the ball is the same, the "feel" is not the same. Comparing a hand drop onto the thigh just doesn't get the true "feel" of a pendular swing over a greater distance and a longer time.

Your "suspicion" that my pendular length changes during the backstroke to lengthen the pendular rod is just that -- your suspicion. I can only assure you that by teaching a natural full arm hang, no hands, and a stable pivot position during the stroke, that I always pay close attention to NOT allow this sort of change in the shape of my "triangle." There is no "play" left in the system with which I could "extend" the radius of the stroke greater than 54 inches. I teach this explicitly every day, but you don't seem aware of this. The putter NEVER rises less than 1.35" in a 12" backstroke when I do what I teach. I avoid artificially keeping the putter low and just don't raise the hands or stick the arms and hands any lower -- there is no change at all in the triangle shape of my setup during the stroke.

I can only assure you that I know the difference between the feeling of letting an arm drop to my side by gravity alone following lifting and holding the arm out 12" from the side and then RELAXING the muscles that were holding it there from the feeling of TORQUING the arm down to impact against my side. In the same manner of paying attention to the feelings of the body in relaxation versus torquing down with muscles, I am also keenly aware of the difference of the feeling of dipping the whole shoulderframe to position the triangle of shoulders and arms back and under the pivot to position the putter 12" back and then RELAXING the muscles that were holding this triangle at this backstroke position so that the whole triangle drops freely back to level equilibrium, versus the feeling of TORQUING the triangle down at any point in the return to level, specifically including torquing the triangle at the very beginning of the return down.

It may be a subtle difference TO YOU and hence cause you concern and doubt and suspicion about confusing the two feelings, but it is not a subtle difference at all TO ME. It's black and white, night and day, to me. One is a NON-voluntary releasing of the tension of the triangle being HELD stationary at the top of the backstroke, while the other is a voluntary ADDING of tension to torque the triangle down from its stationary holding. Big difference.

Moreover, as Crenshaw experiences it, so do I -- the only toquing is at the beginning of the takeaway, with a ballistic tossing back of the triangle with as much smoothness as the situation allows. ("Once I start the putter back, it feels as if the stroke completes itself.") After this initial toss back, the triangle coasts upward and backward under the retarding influence of gravity (ONLY) until the putter head reaches a transitional pause at the top of the backstroke (like a tennis ball toss for the serve). Then the triangle starts down under the influence of gravity (ONLY) and gathers velocity over around a half second swinging back to the bottom. This simple one-toss-is-all-the-voluntary effort stroke will send a ball 7.2 feet across a Stimp 10 green, with my putter. Every time.

Now let me focus more closely on one specific sort of "feel" -- the putter handle in the hands. In a free-fall pendular swing, the hands and the handle inside the hands are moving in the same direction and under the same acceleration, just like (handle) riding in a car (hands of grip form). Acceleration down, however, is not the same as acceleration horizontally across a gravitational field. Since there is SOME CHANGING BLEND of accleration down and across in a pendular swinging down and under and across, there ought to be a CHANGING BLEND of acceleration down and acceleration across. The lower the putter head swings towards the bottom, the MORE the accleration is horizontal and the less it is vertical. This matters to what the hands "feel". The hands do not feel anything at all in a free-fall vertical drop of hands and handle together. But as the hands and handle start to gain horizontal acceleration, do the hands feel the handle "pressed back into the seat"? The answer from physics is: "No, not if both the handle and the hands are undergoing the SAME FORCES bringing about the acceleration of both at the same rate. And they are. The only FORCE in this sort of swing is gravity, acting jointly the same on the hands and the handle inside the hands.

But when there is torque bringing the putter down with force of the arms-hands, then there are forces in addition to gravity, and the force of the hands acting of the handle "presses the handle back into the seat of the hands" as an acceleration of a car down a horizontal road will press the occupant back into the seat. Here, the hands' tactile receptors will "feel" the handle's pressure more against the back side of the grip of the two hands and less on the front side of the hands. That's the feeling of "shoving" the putter handle along the swing arc. (You could also feel a "pulling" of the handle along the arc by the lead hand and arm.)

When a golfer does not torque the putter handle down, he instead "rides" the handle with his hands and with his turning shoulder frame. Riding the putter down may or may not require the golfer to move the shoulder frame so as to "keep up" with the handle as it swings freely down. But if the golfer has to "move" the shoulder frame to preserve or maintain the sensation of "nothing changing" inside the hands, then he may think of this as a feeling associated with torque, but it is not, since he is in fact not imparting a torque to the putter by simply keeping up with the handle to "ride it down."

If you do NOT feel this extra pressure of the handle against the rear palm, you are ipso facto not torquing the putter. That's exactly what I teach and experience -- to ride the putter down and experience "no change" inside the hands coming down to the bottom. It's not physically possible to torque the putter down with arms and hands and still experience "no change" coming down. Since I always attend very carefully to whether I feel anything in the hands coming down, and I don't, then I COULD NOT BE TORQUING the putter in the downstroke.

Your suggestion that human tactile sensitivity is not sufficiently accute to detect these sorts of "feelings" does not take into account data from modern psychophysics of human perception. Human fingers, palms, tongues, and lips are the most sensitive areas of the skin. Human skin can detect a deformation of the skin of as little as 0.001 mm or 0.00004 inches, and the human fingers of male adults can detect two points of pressure as separate even though separated by as little as 3-4 mm, compared to forearm sensitivity of about 10 mm and shoulder sensitivity of 40-45 mm.

When the putter is moved by torque forces of the hands and arms, the inertial properties of the putter itself generate "stress", "strain" and "shear" deformation by pressure of the handle against the skin of the palm and fingers and fingertips. When the putter is deliberately stopped at the top of the backstroke, as opposed to allowing the putter and hands jointly to coast to a stop under the gradual slowing of grtavity only, the putter handle tends from inertia to go past the stopping point, and this forces the side of the handle against the lead-side palm with greater pressure, and also places a shearing pressure between the flat of the putter handle surface on the top and the thumbs tips. Any golfer can detect these changes in "feel" if he chooses to attend to them.

The more the golfer sets his ideal as "feeling nothing change" at these transitions and during the downstroke, the more his motion pattern has the hands and putter undergoing the SAME gravitational forces only, as there is no added force of torque from the body moving the putter outside / faster than this pattern. The "feel" of "nothing changing" is a lot clearer kineasthetic cue to the tempo of the stroke than any effort by the golfer to gen erate a specific level of pressure of the handle against the rear palm in the downstroke.

You should pay more attention to the consequential feel in the hands of torquing the putter down to see what I'm talking about.

In addition, since I also teach that the putter head ALWAYS arrives at the bottom in the same timing that a free pendulum would arrive, and since I attend very carefully all the time to whether this is so, and it is so, then I must not be accelerating the putter any faster than gravity accelerates it. Again, it is not possible to preserve this timing and also be torquing the putter down. The only question is whether my putter arrives sooner than a pendulum downfall would have it arrive. It doesn't.

I also teach that timing matters, but "feel" does not. To illustrate this, I use what I call a "Quasimodo Stroke." This stroke is made with great tension and malformation of body posture, but nonetheless adheres to the timing of an instinctive, gravity-sponsored stroke ("one potato" back and "... two" to impact). So long as Quasimodo adheres to the timing, his "feel" is utterly irrelevant to distance control. The only variable that matters is putter head velocity at impact, and the backstroke size plus the timing guarantees that this will result correctly despite weird "feel" in the body. Counterintuitive perhaps, but nonetheless true. If you use "normal" grip and postures, you simply cannot "torque" the stroke down and still match up the movement timing to a gravity-sponsored stroke. If the timing is what the timing in a gravity-sponsored stroke should be, then ipso facto you COULD NOT HAVE TORQUED the stroke down.

You should learn the timing of the pendulum downfall and then pay attention to the downstroke timing of your putting stroke. It's simple: if you're early, you are torquing. If you're on time, you're not.

The "feel" of this sort of stroke is a blast-off toss or shove back and then nothing at all but the feel of the triangle freely swinging in gravity as it will, back and then down.

Just toss your arms back and up from your sides and DO NOTHING except wait for them to flop back to your thighs. Try to make the toss back last "one potato" to the point of directional transition at the top of the "backstroke." You should start to notice the difference in feel of the dropping without torquing and the feel of "bringing" the arms back against the sides with torque.

Cheers!

Geoff Mangum
Putting Coach and Theorist
PuttingZone
http://puttingzone.com
Golf's most advanced putting instruction -- you're either in the PuttingZone, or not.

On the issue of "drop" heights and timing, I agreed with you on this on the other topic thread, but to reiterate:

Based on your 54" pendulum swing radius, the quarter period is 0.59 seconds regardless of the "drop" of the pendulum ... with the velocity at the bottom varying with height of the drop. An equivalent vertical drop is ~67" for 0.59 seconds of pendular timing ... so the 1.35" rise on a 12" backstroke elevation is not an issue. However, the velocity at bottom impact is an issue because this raises the issue of distance being a function of backstroke length for pendulum putting.


The length of the putter backstroke arc length must be a function of the amount of initial torque applied to push back and raise the putter head. I believe you state that the length of the backstroke is inherently felt and the initial torque applied will get it back as far as in felt necessary to achieve the final velocity at impact and the desired distance. So what you do at the very start of the backstroke will govern the velocity of the putter at impact.

So we have an initial breakaway and consciously applied torque to start the backstroke and with enough energy to get the putter head to the proper height and arc distance. Then as the putter head approaches reversal it's energy is all converted to potential energy as it stops ... and then .... one only need "ride" the pendulum to impact.

This implies that a downstroke "internal" torque must be applied to the mass of the torso, shoulders, arms, hands to ensure that you keep up with the free-falling putter as it "gathers velocity" ... to it's final impact solution. How does one balance the internal body torques with the pendular putter downstroke (or downfall) acceleration ??

How does one quantify and qualify the "feel" necessary to create the initial backstroke torque and the internal downstroke torque ?? It seems that the initial decision is crucial to the final outcome at impact.

On one specific point of the forces within the hands, please address your comments on the loading within the hands in the sagittal plane to continuously support the cantilevered putter .... and not only looking at the pendular swing in the coronal plane. Obviously the hands are constantly loaded vertically from the dead weight of the hanging inclined putter, while you are generating torques and rotations in the lateral swing plane. How does the mix of constant vertical forces and free-falling pendulum momentum apportioned in the overall feel of the putting stroke ??

I don't mean to be obstreperous on these issues, but you have provided no experimental testing results to back up your calculated solutions to your personally perceived pendular stroke mechanics. Measurement of arc lengths, putter elevations, relative position of arms, hands and putter through swept angles, velocities at impact, even compression of the ball at different impact velocities .... and more factors for a proper testing protocol seems to be necessary to make your case.

Do you have any objective testing results to back up your theories ?? If you do please provide them. Thanks in advance.

(I hope you don't say that "da proof is in the pudding" .... LOL .. !!)

Dear Sammy,

I only have time right now to respond briefly. In general, your approach to putting is limited to the physics, and to "proof" in the nature of physics experiments, and this is only the beginning of putting. The physics proof is rather obvious, but the putting proof is pretty elusive.

To "prove" that what I teach is better than what you suggest requires that you know enough about designing human experiments to elicit meaningful data. In the case of mechanics in physics, defining the phenomenon to test and the method for securing data is trivial these days, and has been since at least Newton's days. I have tons and tons of "proof" from the neurosciences about how the perceptions work for accuracy and usefulness in human action, but I'm afraid trying to explain all that to you would be a huge undertaking. For example, the "proof" that the human visual system has timing requirements for "accommodation" (focusing the lenses at a new distance of interest with the ring of muscles surrounding the lenses, a process that takes about 1 second for adults) and similar processing tasks, or that the cerebellum is vital in many timing and movement smoothing processes, or that the typical adult has a "cone of error" of about 8 degrees at the vertex within which his actual shoulder movement trajectory is plus or minus the targeted trajectory 90% of the time based upon "neuronal populational vectoring" processes is readily available in standard neuroscience sources. What the human actor does in putting involves many, many other factors than simply physics. These factors are not susceptible to the simplistic sort of "proof" that you seem to require, at least not without a federal budget.

But if you want "proof" from results, ask any of my students whether what I teach improves their putting skills dramatically in comparison to anything else available or currently being used by golfers in general. That said, I don't in the least shy from "proving" what I say, but frankly I don't have the time to satisfy you in this particular manner. Maybe later.

Responding seriatim:

"The velocity at bottom impact is an issue because this raises the issue of distance being a function of backstroke length for pendulum putting.

Very true! You just don't know what I teach to generate the correct backstroke for the distance on the green. I teach how the human body and brain do this by instincts.

The length of the putter backstroke arc length must be a function of the amount of initial torque applied to push back and raise the putter head.

Your phrase "a function of" is not really appropriate. The brain doesn't calculate torque, but simply orders up a certain charge for a ballistic muscle firing. The motor cortex handles agonist ballistic muscle firing, whereas the cerebellum handles (among other things) the agonist-antagonist muscle coordination and braking process that smooths out the timing and stopping of a movement. This process is very timing critical, and testifies to the equisite timing capacities of the brain and the cerebellum in particular, at least on the scale of 1/10th of a second or so. The interesting thing about the backstroke is that it is ballistic only, and does not entail braking or even smoothing.

I believe you state that the length of the backstroke is inherently felt and the initial torque applied will get it back as far as is felt necessary to achieve the final velocity at impact and the desired distance.

No I don't say that it is "felt" -- this term is the empty and confusing jargon that I constantly have to straighten out. There is absolutely no "feeling" in advance of how far the backstroke will eventuate, mainly because the cerebellum does not participate in conscious experience. The proprioceptive information provided to the cerebellum during targeting is the cherry on the sundae, but the brain loaded for distance in making a putting stroke is not associated with a "feeling" in the conscious mind. Nor is it associated with a "sense" of the forthcoming motion in the "sub"-conscious mind. The cerebellum and these processes are not conscious or even "sub"conscious -- they are NONconscious processes akin to the biochemistry of the kidney. You look to the target and pullk the trigger in the preexisting tempo, and the backstroke length simply results. You witness it happen.

So what you do at the very start of the backstroke will govern the velocity of the putter at impact.

No, what you do to inform the brain about the tempo you will use and the conditions of the green and the target's distance governs the velocity of the putter at impact. All the golfer does is pull the trigger so that the backstroke lasts the right count.

So we have an initial breakaway and consciously applied torque to start the backstroke and with enough energy to get the putter head to the proper height and arc distance.

No, not "conscious" in the least.

Then as the putter head approaches reversal it's energy is all converted to potential energy as it stops ... and then .... one only need "ride" the pendulum to impact.

yes, pretty much that's it -- look and pull the trigger within the tempo, then the stroke completes itself coming down, but you do want to "help" the stroke finish nicely against gravity.

This implies that a downstroke "internal" torque must be applied to the mass of the torso, shoulders, arms, hands to ensure that you keep up with the free-falling putter as it "gathers velocity" ... to it's final impact solution. How does one balance the internal body torques with the pendular putter downstroke (or downfall) acceleration ??

The brian has been trained by eons of evolution to move in gravity and to know deeply gravity's tempo for the human scale. The natural swinging of the arms in gravity is not far off the downstroke in putting, so your puzzlement at how a human gets this done is unusual, from the point of view of common sense. Alas, almost all golfers find this naturalness of "fit" of the human to a putting stroke weird and difficult to understand.

How does one quantify and qualify the "feel" necessary to create the initial backstroke torque and the internal downstroke torque ?? It seems that the initial decision is crucial to the final outcome at impact.

There is no "feel" to quantify or qualify.

On one specific point of the forces within the hands, please address your comments on the loading within the hands in the sagittal plane to continuously support the cantilevered putter .... and not only looking at the pendular swing in the coronal plane. Obviously the hands are constantly loaded vertically from the dead weight of the hanging inclined putter, while you are generating torques and rotations in the lateral swing plane. How does the mix of constant vertical forces and free-falling pendulum momentum apportioned in the overall feel of the putting stroke ??

The hands hang naturally with the forearm out of vertical due to adult muscle development about the elbows, but the hands themselves hang vertically in gravity. This arrangement presents the hands to the tilted angle (lie) of the handle so that the foresarm matches the shaft and the lifeline of the hand matches the edge of the handle. The hands are not "held out away" from the natural hanging position in gravity. yes, there is some cantilvering, but the minimal muscle tone adopted at address is sufficient structural support during the stroke that nothing further is needed.


Cheers!

Geoff Mangum
Putting Coach and Theorist
PuttingZone
http://puttingzone.com
Golf's most advanced putting instruction -- you're either in the PuttingZone, or not.