This question deserves quite a bit more of a response than I have time for at the moment! Let me just say, "yes", and "no."
"Yes," thinking is ultimately not good for a putting stroke, but your statement that cognitive learning leads to thinking in the stroke is not quite the final word. You can first learn what works (at a cognitive and kinesthetic level) and then learn not to think while making the stroke you believe works.
"No," simply modelling a stroke visually is not good enough. The "monkey see, monkey do" mode of learning is obviously heavily relied upon by all primates, but so is the learning process of solitary experimentation to discover what works or what works better or what works best. There may be some of both in learning a good stroke, but my experience has been that watching top putters on television and video doesn't reveal a lot to me about the combination of tempo and movement feelings and thought processes of the golfer. I'm sure that approaches like Sybervision are helpful, but they are hardly self-sufficient approaches for someone trying to master a skill or set of skills. If that were really the case, that's all that pro golfers would do -- watch Sybervision tapes of the best putters. (What would the best putters watch?)
Bobby Locke in the 1930s certainly did not devise his putting technique based upon watching others, although he learned "hooding" from Walter Hagen and learned something about the total tempo and stroke pattern from Bobby Jones. But his stance and path and and finishing movement were his own creation. He was trying to bring about certain features (square face at impact, face management in stroke path, up-stroke thru impact, inside-out path into square on-line impact, avoidance of cut stroke, etc.) that he wanted as a cognitive matter -- a matter of conscious, deliberate choice based upon his personal experience from solitary experimentation for what works best. Leaders in the development of putting technique are always working on this cognitive level in trying out various apporaches to getting better (e.g., Walter Travis, Bob Charles, Paul Runyon, Harold Swash).
There are brain-based reasons to explain why simple visual modelling is not sufficient, mostly from
the function of cognitive structures about "what works" in allowing upward, continuous learning from the valuable interpretation of feedback and the self-monitoring, self-correcting this allows as your experience grows;
the role of cognitive structures about "what works" in maintaining stroke consistency and accuracy in a "grinding" mode for better results over the long haul of a full season; and
the role of cognitive structures about "what works" in preserving self-efficacy and confidence under pressure and avoiding doubts about what to do from one situation to the next.
While there are clearly golfers who enjoy success at a high level without a lot of cognitive structure in their putting technique, their success comes in spurts and does not last their whole career and does not exhibit a steady improvement (so long as the body isn't seriously deteriorating). They are more at the mercy of the changeable body functions, moods, and the fickleness of streaks and slumps. This is not the case with master putters.
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