Dear Chris,
Depending upon how you bend, hold, and stroke the belly putter, the amplitude of the stroke for a 6-foot putt could well be no different from the stroke with a conventional 35-inch putter. I would bet that the belly putter seems to have a shorter stroke, but that this is due to how your hands are placed on the putter. If your elbows are crooked in holding the putter, as opposed to hanging down in a relaxed fashion before moving the hands inward to take up the grip, the sensation of the stroke as registered by the sweep of the hands back and thru would seem small. Holding the putter lower gives a wider sweep of the hands back and thru -- much closer to the "feel" of the stroke for a 6-footer with a conventional putter.
Of course, I'm shooting in the dark here, never having seen you putt. But if you make the stroke of the belly putter with your shoulders rocking back and thru, then the shoulder motion will be very, very close to what it is with a conventional putter. In both cases, the shoulders don't move that much to begin with. On a 6-footer on a medium fast green, the lead shoulder in the backstroke would drop only about 2 inches. The putterhead would probably sweep back 10 to 12 inches. The lower the hands down the putter, the more the hands would sweep in the stroke.
Paying attention to the movement of the lead shoulder is not normal, so you have to remind yourself to feel it in the stroke. If you compare the feel of the shoulder moving with the belly putter and a conventional putter, I suspect you will see that the hand position you have been using is higher on the belly putter but the strokes are not too different, really.
Let me know if I am at all on track here. If not, we'll go another way.
Cheers!
Geoff Mangum
The PuttingZone.com
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