[Daryl]

That 'the' plane is not represented by any body part, but by the force that you are generating in your motion.

Per 2-F (caps and bold added by me)

".... the longitudinal center of gravity, the LINE OF PULL of Centrifugal Force"

"Plane Angle and Plane Line always refer to the center of gravity application"

What that means in effect is that you are "hugging the flail" described in 2-K, when looking at this FORCE that is moving around your center of balance.

That FORCE is most clearly represented by the path of the hands, the pressure points.

Learn to feel your pressure points. Learn to see the plane as the path of the pressure points around your center of balance.

The applauding crowd still standing in admiration as Edz takes the stage and accepts his "TGM Excellence" award. As he takes the podium, the crowd settles into a quiet whisper. As expected, he first thanks his mentors and lavishly praises all of the little people who have helped him along his path to knowledge.

Very good answer.