[Yoda]

I met a pro a few years ago that has a swing technique that is supposed to be back friendly. It seems to defy much of the geometry that we view as very important in TGM, and really in most golf instruction.

The backswing shoulder turn should go no more than 70 degrees. The idea of the plane is different also. The flashlight would point to the line the feet are on, with backswing and downswing. He wants a vertical pick up of the arms on the backswing. He does want a Flat Left Wrist.

At the finish... there is an up move, similar to the Stack and Tilters.

The club obviously does get on plane eventually, or it would not strike the ball.

He has produced numerous good players... including his son D.J. Trahan on the P.G.A. Tour.

This would be a Class "X", but what do you make of this?

[Bold emphasis by Yoda.]

I'm not sure this would be an "X Classification" Variation, Lagster. In fact, it appears to be merely the Turning Shoulder Plane (10-6-D), and probably the Left Arm Swing Plane version -- as opposed to the Vertical Wristcock version.

Here, the Arms produce the vertical element of the Stroke and point a line inside (but parallel to) the Plane Line. [This would be Mr. Trahan's "foot line".] As the Arms simply lift and lower the Club -- the "vertical pick up" -- the Pivot takes the Hands directly to a Squared Shoulder Plane at the Top. This steep Backstroke brings the Club into its Loaded condition on a Vertical Plane at the Top (and not on the Inclined Plane). And Single Wrist Action (10-18-C-#3) produces Hands that are "well under" the Club (and thus not 'Palms aligned to Plane').

This "straight back" Backstroke is mirrored by a "straight down" Downstroke. The "upward thrust" you mention would be the Pivot's 'equal and opposite' reaction to the Arms and their vertical force.

It is not surprising that Mr. Trahan has produced champions with this Stroke Pattern. Quoting Homer Kelley: "It is extremely effective and dynamically correct."