[Mathew]

How many "TGM shifters" truly have their tip/butt ends really pointing at a single plane line during the shift?

Well strictly speaking none of them because the butt end of the club doesn't exactly point at the plane line unless the sweetspot has rotated and thereby putting the shaft onplane as well as the longitudinal center of gravity.

Unless it happens near instantaneously around club horizontal to the ground/parallel to plane line then a shift is almost always off plane until it re-establishes a pointing-at-the-plane-line position.

These are not the precision alignments of the golfing machine. It is merely offplane. Whilst you can get away with being offplane in the backstroke, find an alternate downstroke plane or readjust at the top back to where you should be, this is not the prefered way. On the downstroke you must be in a position to drive the clubhead to a point on the plane line. Even with a plane shift, the force goes downplane towards the line on a plane and is one of the three essentials..

That is what I mean by drift - a gradual off plane movement which is needed to re-establish on plane shaft/sweetspot plane after a shift.

Or you could do it the proper way and shift and be onplane whilst your preforming the shift at the same time. The plane line does not change, the plane angle is adjustable....otherwise the clubhead orbit becomes 3 dimensional and the precision vanishes.