I don't have the book at work, but read 7-3 when you have a chance. It is truly amazing how important the Right Forearm is with regard to TGM and how it is neglected in "traditional" instruction. 7-3 to me is one of the best sections in the book. From 7-3 you get many elements that the Right Forearm contributes to the Stroke.
The On-Plane Right Forearm at Impact Fix shows you:
1. Angle of Approach
2. The Inside-Out Impact (the Forearm points at the inside aft quadrant of the ball)
3. At Fix, since the Right Forearm is in the same plane as the Clubshaft, you get an idea of the angle of the Inclined Plane.
4. Through PP1, the Right Forearm stretches the "wobble" out of the left shoulder and give structure to the Power Package.
5. The Right Forearm traces the Plane Line through PP3.
6. The Right Forearm "Pick Up" gives you the simultaneous Back, Up and In Start Up.
7. The positioning of the Right Forearm via the placement of the elbow gives you the Basic Pitch, Punch and Push Strokes.
8. In Hitting, somewhere in the book not exactly sure what section, the Right Forearm is "Muscle Power" needed in executing Hitting Procedures.