Dear 300Drive,
The shoulder joint has a very wide range of motion, especially in the direction across and away from the frontal plane of the body in a transverse way. The reason the shoulders are generally set up square to the line is to promote square impact (the same as at address) and a motion of the limbs thru the impact area that is straight at impact and for some distance on either side of the ball. The squareness of the shoulder setup also promotes consistency.
But it is perfectly possible to make a straight putt with only one shoulder being involved. Professor George Shoane at Rutgers has performed studies of right-hand-only putting, and Dr Tony Piparo of
Down the Line Golf has designed a putter for use solely with the right arm (for a right-hander) while facing the hole. And the "Claw" grip taught to Chris DiMarco by Skip Kendall, who learned it from an elder in Wisconsin, basically is a left-arm-only stroke to the extent the movement of the putter is really controlled in the shoulders without independent arm action.
The true fundamental is square putter face moving straight thru the ball to the target at impact. Building up from the putter face into the body, this recommends that the back of the left hand mirror the putter face orientation at setup and impact, and this further implies that the two forearm bones of the left arm make the top of the forearm mirror the orientation of the back of the left hand. To make this orientation repeat at impact, the movement of the left arm back to the top of the backstroke with a shoulder rock (left shoulder down) will necessarily move the right shoulder up. If you can visualize the TWO shoulders in coordinated motion in three dimension of space plus time, the fact that the right shoulder is offset closed a little at setup does not mean the two shoulders cannot move in the same plane of motion or that this plane of motion can remain "square" to the putt line in that the intersection of the plane of motion and the green is a line paralleling the putt line.
For example, if the left shoulder moves vertically down, the right shoulder CAN and WILL move straight up, even if the starting position of the right shoulder is a bit back, or closed. The real "twist" in the body is not along the shoulder line but in the waist and lower back. A little twist is not a big deal, but too much twist moves the chest off plane so that the left side of the chest gets too close to the ball, in a closed setup.
Bobby Locke setup really closed, with the right foot drawn back from a toe line paralleling the putt line by about 4 inches. This reorientation of his hips twisted his torso closed. he took the putter back along the closed line of his toes but then in going forward, his right shoulder moved laterally out towards the putt line, effectively resquaring his shoulder to the putt line just before impact.
So you have a number of options:
1. With a mild degree of closed shoulders, just ignore the starting position and focus on the shoulder motion staying in plane and moving the left arm straight at the target thru impact with back of hand and top of forearm aimed square thru impact.
2. Open the hips and feet to the same degree the shoulders are closed to resquare the setup, and again focus on the shoulder action and the movement of the left arm.
3. Add a little right-shoulder motion forward in the downstroke a la Bobby Locke (pretty dicey, takes years to perfect).
4. Use more of a combined shoulder-arm movement of the left arm, in which the left arm moves somewhat independently of the left shoulder, as this shifts the brain control of the motion as a whole from the shoulders to mostly the left arm and side-steps the issue of the right arm.
In any case, I would suggest working on the squareness of the face of the putter thru the impact area -- trying to make a shoulder-powered move that naturally allows the left shoulder to rise past the bottom of the stroke in a manner that brings the left arm along behind it so that the putter head and face moves squarely down the line.
Cheers!
Geoff Mangum
Putting Theorist and Instructor
PuttingZone
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