Dear Rich,
You really need to trust your body and move your body, not the putter. If one posture is better for this than another, then that posture is probably better for your stroke. In the setup, the main things you're looking for are: 1. a flattened putter sole that presents the handle to your relaxed, hanging hands; 2. hand position hanging naturally so that, if you have your grip on the putter handle and let go with the rear (right) hand, the right hand will swing ONLY sideways, and will not fall father away from you (meaning you are too close to the ball) or fall closer in to your legs (meaning you are too far back from the ball); and 3. your eyeballs are aimed straight out of your face, regardless of whether your eyeballs are vertically above the putter or slightly inside the putter, as this doesn't matter much if the "gaze" is aimed straight out of the face, because a straight-out gaze and a rotated head turn (apple on a stick) runs the line of sight in a perfectly straight line on the ground the same direction the putter face aims.
So sometimes, to get all three working together, I advise: ALWAYS flatten the putter sole to begin with; then, whatever the length and lie, the putter will present itself to your naturally hanging hands in a specific way, and you can step up to this handle and your hands "fit" onto the handle so that the right hand (if relaxed off) will swing ONLY sideways. That system will work with even a length and lie that is not the best for you, so long as you can still adjust your torso bend and upper neck bend so that a straight-out gaze actually starts out pointing at the ball. In other words, you can adapt to using even a putter that is not really best for you (in all three ways) by getting two of the three good, and let the neck position make up the "fit."
If you want all three to be proper, you should get "fit" for a good setup for targeting and stroke. That means you should first have a good setup: 1. a comfortable upper torso and neck bend that aims the straight-out gazing eyeballs at the ground a certain distance out from the feet (not less than the distance from the center of your shoulders to your eyes, measured from the balls of your feet straight out away from your feet to your front -- 8-10 inches for most males); and 2. hands hanging naturally, which usually means slightly out forward from the line from shoulders to balls of feet -- the hands most often hang above the tips of the toes. This setup lets you target accurately (head-eye gaze and comfortable position, even if not directly above the ball) and lets the stroke proceed in a natural way with least need to manipulate the arms and hands. If you stood there looking at the spot where your line of sight hits the ground, then that is where a good-fitting putter's sweetspot should also be, and where your hands hang is where the good-fitting putter's handle should fit into your hands. If you do this (setup first, then putter fits these two places -- eye sight hits ground=sweetspot, hands hang=putter handle with right hand swinging off only sideways), this results in a flat, properly soled putter in a comfortable posture for both targeting and stroke.
If you are in this setup with a putter that fits this setup, then you need to like making a stroke with this "look and feel." To put it bluntly, if this good fit and setup is not something you like the "look and feel" of, you probably should change what you like. it's not that hard to do, as success slowly breeds affinity. It could be mostly that your head-neck posture with a good-fitting is not something that feels really nice. I can only advise you to experiment some with the head-neck posture between a neck that parallels the ground (forehead at same elevation as chin) to a head-neck that is more tilted up (forehead higher than chin). Wherever you end up liking the head-neck posture, then with hands hanging naturally, the putter needs to fit this and sole flatly.
Sometimes it's a trade-off. It would be the ideal if your hanging hands AND neck posture ended up lining up the shaft of the putter with the bones of your forearms when the sole is flat. That's about as good as it is likely to get. If any one of the three has to give, it is probably best to let the head-neck bend give while keeping the gaze aimed straight at the putter sweetspot.
This is where the issue of "look and feel" of the putter in your setup crops up -- when the head-neck seems fine but the putter shaft extends back from the flatly soled putter head to the hands on an angle flatter than the line of the forearm bones, OR the putter shaft comes to the hands on the same line as the forearms but the head-neck posture seems too bent over (even if not bent farther than parallel to the ground). Either of these "discomforts" render the "look and feel" of the putter in your setup a little "off." Getting the head and hands on the same page is best, but not always possible without compromise. If you have to compromise, then you have to learn to like the "slightly off look and feel" of this putter in your setup.
What I sometimes do is get a putter that is too flat for me and learn how to like it. That means learning how to move THE BODY so that the sole of the putter moves thru the impact zone "flush" in relation to the surface. Basically, it means moving the shoulders in a single plane of motion without any independent use of the hands or arms. This single-plane (vertical or tilted) movement of the shoulders will keep the too-flat putter moving square and straight thru impact. You should train yourself to feel this movement with your eyes closed -- where and how do the shoulders move in a single plane, leaving the line of the neck from base to chin steadily aimed perpendicular to the intended line of the putt (and the aim of the putter face at the beginning). You don't want the upper torso twisting back around right, then back around left. Instead, you want to send the shoulder back and under on a line, even if on a slant. (The same slant as the putter shaft is a good slant to choose, if you don't like a vertical shoulder action). In this movement, you want the sensation that the base of the neck (where it meets the shoulder frame) is not getting tugged out of plane. When you do this, the focus is upon the use of the shoulders and the steadiness of the neck line, not on the "look and feel" of the putter.
So, the primary value is a properly flattened putter sole. The next most important value is naturally hanging hands and a shoulder-only action. The final value is head-neck comfort, but in every case a gaze that aims the eyeballs straight out of the face at the ball and putter sweetspot.
I hope this helps.
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.
