Dear bgolfing,
Where the butt of the putter points differs depending on how a specific golfer holds a specific putter, so it varies a bit exactly what spot on the body the butt points toward. But if you think of the putter shaft as establishing a plane that slices your body into left and right halves thru your sternum, this plane stays centered in the back and thru motion of the stoke. Often, the golfer will hold the putter so that the line of the forearms matches the angle of the shaft when the putter sole sits flat on the surface. In this case, the butt will point more or less at the bottom of the sternum. (This is why belly putters often get anchored there.)
The way to "feel" this during the stroke is to move the shoulder frame, not the hands. If the shoulders power the stroke with a rocking of the lead shoulder down and under and back beneath a stable neck line (like the top bar of a swing set, the arms plus putter as a unit being the swing that hangs beneath the bar), the hands go only where the shoulders send them. There is no independent moving of the hands farther or faster than where the shoulders send the hands. The arms, the hands, and the putter all get moved solely by the shoulder frame. The muscles that move the shoulder frame are in the midsection and the lower back, where the upper torso is connected to the skeletal frame of the lower body (pelvis and thigh bones). So the arms and hands stay relaxed at a steady-state grip pressure. Actually, the shoulders and top of back and pecs also share in the same "grip" pressure. There is a unified muscle tone that perfuses the whole structure of the shoulders, arms, and hands, and this muscle tone does not really change during the stroke, since these muscles don't move anything.
If the arm pits are opening and closing noticeably in the stroke, then the arms and hands are getting ahead of the shoulders. The same is true of wrist folding -- this means the hands are getting ahead of both the shoulders and forearms. The same can be said of the elbows -- any folding here means the forearms are getting ahead of the upper arms and shoulders. So the standard lore that advises you to "keep the triangle intact" is just a crude way of saying "move everything together by moving the shoulders only."
Another way to get a sense of this is to take a magazine or sheet of cardboard and press both hands flatly together to hold it in your putting posture instead of a putter. Then make a stroke that keeps this "plane" slicing the middle of your body back and thru.
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.
