Analysis

[lagster]

Do you think the term "plane shift" is apt when what most /all people do ( including Leadbetter - hence your X classification) is a "plane drift"?

Plane angle can readily be defined at 4 points in all swings.

1. Address

2. Left arm horizontal to ground

3. Top/end of backstroke

4. Impact

plus maybe Follow through/ both arms straight.

Most golfers ( I would argue all golfers) drift planes between these positions. During drift the butt/end of club rarely points at target line unless the drift happens rapidly around clubshaft horizontal ( and therefore ideally parallel to plane line).

Leadbetter people basically are double shifters - categorised by their address / impact location and top/end of backstroke positions. They may drift a bit more than others off TGM plane at left arm horizontal but 90 % of people drift not shift!

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I think I understand what you are saying about PLANE DRIFT. Some do seem to do as you describe.

An extreme example of this, I believe, would be the PLANE philosophy of Don Trahan, known as THE SWING SURGEON. He wants the butt of the club to point at the LINE YOUR TOES ARE ON, throughout the BACKSWING, and most of the DOWNSWING. His son, D.J. Trahan, on the P.G.A. Tour, does appear to do something like this.

He teaches a variation of a SWINGING PROCEDURE, and some of his students do very well. His technique is supposed to be easier on the back.