[HungryBear]

Trying to get this back on track .

If we equate this to a triangle model with the angle formed by the left arm and the line of the shoulders representing the lever in question . Then the left shoulder is the point where the two lines meet obviously . Any lengthening in the Right Arm increases the angle at the left shoulder and vice versa.

So agreed the "any point of contact" seems outside of a pure or simplistic 2D geometric model. For the golfer whose motion is 3D the point of contact between left arm and chest will change for different shots. Depending on the amount to which the left arm is raised vertically and the length of the swing etc etc.

Is Homers "any point of contact" an effort to help us locate the angle on a human golfer given the various places it could be formed for different strokes?

No disparagement at all intended to HK's work, He has the application of #4 soo right in many places. BUT. I suggest he might give renewed thought to 6-C-1 #4 and the drawing. In words I would say it is "that piece of rope" that fastens shoulder to upper arm is PP#4 and #4 accumulator is the angle between arm and shoulders just as described. I do not like to think about "ANY point of contact".

HB