Yes, sir, having the top of the spine flat bor parallel to the surface promotes a flat face, a straight gaze, and free arm swing on the targetline.
But I also say that a straight gaze is more important than a flat face (chin and forehead the same height above the ground). Thus, a head position with the forehead slightly elevated is okay, so long as the gaze remains straight out of the face. Otherwise, you get "optical delusions" about where the hole and line of the putt are really located.
Many people are not comfortable in a flat-face postue. Some have too big a pot belly, some have spine stiffness, some have lower back problems, and some have balance or equilibrium problems with this setup. Golf is a sport for many people of differing physiques and fitness conditions. So, not everyone can "get along" with the preferred posture.
It is also helpful to think of the putting stroke as occuring in a "stroke plane" similar to the "swing plane" for the full swing. If you use a stable stroke plane, the plane will be either tilted or vertical to the surface. You can make either of these stroke movements with or without a cervical spine that is parallel to the surface. The flat head, vertical gaze plane, top of spine parallel to surface, ferris Wheel turn of the head and eyes to the target, and the vertical stroke movement all tend to reinforce and support one another with mutually connected visual and kinesthetic cues. When you start giving up some of these features in the setup and stroke movement, you lose the benefit of the total package. Even so, you can still do some real damage!
Cheers!
geoff mangum
PuttingZone
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