Tongzilla if you can agree with 2 undisputable facts you'll get it....
1) the left shoulder, arm and clubshaft are inline by going to an uncocked position (zero no.3 acc angle) ?
hence the left shoulder is onplane
2) the pivot center that controls shoulder motions is above plane?
Now, explain how since the answer to both these questions is yes - how the left shoulder can be onplane, the stationary center that controls the shoulder motions is above the plane and then still have right shoulder onplane at followthrough ?
Its just basic logic...
I mean have you thought this through. Memorising passages (although they are a good start) won't get you anywhere unless you actually challenge yourself and your assumptions. If you are truely observational, Hunter didn't draw it directly on the inclined plane - he drew it with the right shoulder offplane slightly at followthrough because he couldn't draw it onplane and keep the center above plane....
The way I see it now when looking at the golfing machine - I do my own research into particular areas and without fail, if it is correctly done - everytime it agrees and clarifies Homer Kelley's work and it allows you to appreciate it in greater depth...