Dear Raymond,
I should clarify what I teach about "beside-the-ball" targeting. Basically, I teach NOT to target (hunt for the relationship between ball and target) from beside the ball when determining where to aim the putter face. Instead, I teach to aim the putter face based on behind-the-ball sighting and anchoring those behind-the-ball perceptions of the relationship (line) between ball and target so that once you approach the ball in order to aim the putter face, those perception anchors are right there on and near the ball, so that the aiming of the putter face does not involve a separate, second targeting (hunting to "see" the relationship (line) between ball and target) while standing at the ball.
Only after you have completed the aiming of the putter face do you then square up the body -- not to the line of the putt or anything involving the target per se -- but to the putter face itself, as it has been aimed. That is, the line of the throat from base of neck to chin is set to match the top leading edge of the putter face, this squares the line across the eyes to match the aim of the putter face and also sets the shoulder frame parallel to the aim of the putter face, and then the body downward from the top sorts itself into a comfortable stance in the feet (balanced and stable and even).
So there is NO "targeting" from beside the ball up to this point. Only after you are square to the putter face as aimed are you in a good ensemble of body positions and postures to generate accurate perceptions of the "line" between the ball and the target. But even now you are not trying to "see" a line connecting ball and target. Instead, you are in a position to look along the direction that the aimed putter face points, in such a way that your head turn sends the gaze and line of sight ONLY in a straight line that matches the aim of the putter face. Once the head has turned the face and eyes as far as the target distance, you SHOULD be looking directly at the target -- but only if you aimed the putter face accurately to begin with. otherwise, you will end up after the head turn looking at a spot beside the intended target. This is not "targeting," but CHECKING how well you have aimed the face, or determining after aiming the face as best you canm, where exactly you have pointed the putter face. (I am the only person in golf history to teach how to perform this checking of the puter face accurately, which doesn't say much for golf instruction over the ages.)
This checking head turn does double duty as a final "touch" calibration, also.
At the end of the day, though, even this "checking" from beside the ball does not involve eye dominance. Eye dominance beside the ball matters ONLY if you do not know how to do this checking. This checking is done carefully only after you square up the body to the putter as aimed. So to truthfully and completely show you what I say in response to your exact question, my answer is eye doiminance doesn't matter beside the ball and has nothing to do with setup, so that cross-dominant and same-dominant golfers all ought to target only from behind the ball, aim the putter down this line as anchored near the ball, square up beside the ball based on the putter face, check how they have aimed the putter face and verify that the aiming was done correctly, and then putt straight (the same way the putter face is aiming).
Cheers!
Geoff Mangum
Putting Coach and Theorist
PuttingZone
http://puttingzone.com
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