Dear Greg,
What you describe is a very typical flaw for golfers in putting -- the putterhead going back top the top of the backstroke goes "across the line" of the putt, and then either loops back inside before coming forward or cuts out-to-in across the ball. The basic problem is at the start of the stroke in the way you move the putter back from the ball.
Golfers who use hand and arm muscles to initiate the backstroke in putting -- and they by far are the VAST majority -- usually start the putterhead back by crossing the line. Let me be a little explicit for the sake of clarity.
The "line" I am referring to is the line the bottom of the ball will roll on straight away from the putterface as aimed at address. This "line" connects the sweetspot of the ball (center of the sphere of the ball) with the target in a straight line, connects the bottom dimple of the ball with the target, connects the top dimple of the ball with the target, and is the same as the line that connects the back dimple with the center of the ball and thre front dimple in ther way the ball will be rolled, and is the same line that meets the squared putterface perpendicularly at the putter's sweetspot. If you had a chalkline snapped on the green and placed the ball on the line and aimed the face of the putter through the center of the ball with the sweetspot of the putter directly behind the back dimple of the ball, intending to roll the ball straight down the chalkline, that is the "line" I am referring to.
When I say the putterhead "crosses the line" going back, I mean that the sweetspot of the putter moves farther away from your feet, does not stay on the line, does not stay at least inside the line, but travels outside the line on its far side.
The truly straight-back-straight-through stroke has the sweestpot of the putter poised on this line at address and then the motion in the takeaway keeps the sweetspot of the putter above this line going back and coming into impact, with the face square to the line.
The nature of wrist joints and elbows is such that, from a static position at address, starting the putterhead back with "changes" in the angles of the wrists and/or elbows will usually promote and arcing stroke path. Not only is the path arcing, but depending upon the combination of muscles activated, the path is also likely to start away from the back of the ball across the line. Usually, if starting straight back is like seeing the ball as a clock with the putter sweetspot starting at 6 at the back dimple and the front dimple being at 12, the poor takeaway leaves the back of the ball from about 5:30 in the same direction the clock's minute hand aims when pointing at 5:30 or so. This flaw can be handled by close attention to the starting combination of wrist and elbow (and even shoulder) joint action, but it is not optimal.
A better way to get rid of this initiation flaw is to eliminate ALL limb joints in the takeaway. These joints are the fingers, wrists, elbows, and shoulders. All human movement entails paired muscles changing a joint angle. To crook the finger, muscles pull the finger joint into a crook. To wave the wrtist, muscles pull on either side of the joint to make it open and close. To lift the forearm, muscles on either side of the elbow raise and lower the forearm. To flap the arms, muscles around the shoulder girdle (shoulder muscles and pecs on chest) open the arm and the armpit and then close the arm and armpit. In the flawed takeaway, some combination of these joint changes in the limbs is allowing the putter's sweetspot to get farther away from your feet at the start, so thre putterhead's path crosses the line.
To eliminate these joint changes, just move the lead shoulder socket ONLY down and back. The shoiulder sockets are located for purposes of good balance directly above the balls of your feet. (Stick the butt-end of the handle of your putter into your armpits and see what the putter points at to check this at address.) If your arms and hands are naturally hanging from these sockets with your palms turned back to your thighs, and you hang your putter shaft horizontally in your hands so the putter's butt-end points along the line across the balls of both feet, you can move the putter like a battering ram STRAIGHT BACK and STRAIGHT THROUGH very easily by sending the lead shouldert socket down at the balls of the lead foot and letting the socket naturally rock back above the line across the balls of both feet, and then moving the shoulder socket in reverse over the exact same pattern coming forward and then lifting the socket straight up from the balls of the lead foot. The "battering ram" will describe a smiley face in its motion back and forward, but the entire shaft of the putter will stay aimed on the line across the balls of the feet, and the ends of the putter will not arc back inside going back or going forward. If you are a policeman with a battering ram suspended from your arms intent on knocking in a door by smashing through the door knob itself, your most powerful swing of the battering ram will be straight back and straight through. So in our analogy, you in your setup are aiming the butt-end of the suspended putter at a doorknob just in front of your lead foot, and then swinging the battering ram putter straight back and straight forward into the doorknob.
The mucles that make this shoulder socket move like this are in the lower abdomen and lower back, as these muscles flex the ENTIRE SHOULDERFRAME as a unit, along with the rib cage, down vertically on the lead side joined with up vertically on the back side to send the front socket rocking down at the lead foot and back along the foot line for the backstroke; for the throughstroke, the pattern of motion of the body is reversed, with the only difference being that it takes effort to send the back socket up but none top let it rock back to level. The bacjkstroke is a putting-back effort, but the downstroke is just a relaxing to let the shoulderframe drop back to neutral or level. To finish this stroke, there has to be some effort to send the lead socket ABOVE the level starting position, so this part of the stroke is a lifting of the front socket straight up away from the balls of the feet. The trick seems to be to do all this so that the putting-back and the lifting-up parts are timed to coordinate smoothly with the natural pace of the free-falling downstroke.
But back to why this helps cure the problem of starting the stroke across the line. The muscles used to make this motion leave ALL the limb joints unchanged in the stroke, so nothing gets any longer. It is only when something about the limb or hands lengthen that the putter is able to go farther away from the feet than the strarting position at address. Starting the putter back ONLY with the shoulderframe as a unit insures that the putter's sweetspot will at best stay directly on the line or at worst travel slightly inside the line going back.
If you hang your arms and hands naturally (and don't worry about trying to get the hands under the shoulders, just let the elbows hang straight down and let the hands end up wherever, usually a bit out front from the shoulder-elbow vertical line, more on the balls or toes of the feet) and ONLY concern yourself with moving the front shoulder socket so that the whole shoulderframe rocks in plane, there is no need to even be aware of the hands, much less to manipulate the putter. Try setting up facing a wall with the toe of the putter just a little back from the baseboard; make this stroke and simply observe how the toe of the putter stays close to the baseboard, not getting closer and not getting farther away -- without any manipulation with the hands. This action also keeps the face of the putter square BOTH to the line of the putt and to the path of the stroke.
In your action, it is highly likely you are consciously or subconsciously using your hands to start the stroke away from the ball. Once the sweetspot of the putter has gone across the line, you consciously or unconsciously realize that an adjustment is required, so you "soften" the wrists (both of them)and this folds the right wrist back but merely extends the left wrist (so this is not as noticeable). The precise way in which the right wrist folds is probably slightly askew the line of the putt (not folded back vertically like a pet door in a manner that delofts the face without skewing it out of square), so this opens the face in relation to the putt line. If you pull across the ball out-to-in with a slightly open face, you can achieve a roll that "looks" pretty straight although it starts with a little cut spin (clockwise sidespin looking down on the ball). This sidespin goes away quickly, and is much less important than the face orientation slightly open in causing the ball's resulting direction of roll. For example, a face open a mere 5 degrees but used with a cut-stroke out-to-in path that cuts across the intended line of putt by about 30 degrees sends the ball off pretty straight. This 5 degrees open is a mere 1/18th the way off perfectly square along the way to totally open. If you opened the face 5 degrees 9 times in a row, the face would end up at 45 degrees open, so 1/18th or 5 degrees is not much at all. Other combinations of open face and cut path also yield rolls that look pretty straight.
Because getting the combinations right is pretty demanding, this sort of stroke is not optimal for regular play.
So, to sum up, don't cross the line going back, and the best way to avoid this is to use only the lead shoulder to start the strfoke by pushing straight down at the balls of the feet and then back along the line to the rear foot. The shoulder thus moves the whole system of arms, hands, and putter back as one "triangle" that keeps its shape the whole time. Hand position doesn't matter and hand or arm muscle activation only hurts.
Try this and let me know.
Cheers!
Geoff Mangum
Putting Theorist and Instructor
The PuttingZone
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