[O.B.Left]

Because of the lie of the clubs?
Kevin

Absolutely. The amount of work Daryl has put into this is staggering. But the TSP is a StartDown Plane of Motion. Impact is ideally along the Shaft Plane Angle, the clubs lie angle, which will also be considered an Elbow Plane if the Elbow is also on that same Plane Angle. A very good thing that most truly great golfers achieve at Impact and Homer reasoned the perfect alignment around which to adjust our machines at Fix. This alignment, this RFFW on the shaft plane at address is perhaps the only tell tail sign of a TGM adherent. That and some totally bizarre golf terminology.

Plane Shifts do happen, for longer swings anyways, but the straight line Base Line stays put. So keep tracing my friends. 1-L-18

The plane angle you release along is a function of what plane angle shifts you are employing and at what point you release. Its a flat plane yes, like a sheet of glass, that shifts its angle up and down with the base line staying in place.

Now if you point the entire flat plane, sheet of glass, left or right of the original target and trace the new straight base line associated with this new plane of motion , then you are said to have "bent the plane" or its base line to the left or the right. This new Delivery Path of the clubhead when combined with variations in clubface angles will produce curved shots for instance. You bend the plane to the right to hit a draw say. Meaning your sheet of glass is pointing right and your clubface is pointed left of that to some degree. The geometry stays the same, you still trace the base line, the plane angle changes etc.