[BerntR]

I am pretty sure that in a well executed stroke with a "heavy" right hand on the shaft the right forearm will be on plane whether you're swinging on TSP, EP or something inbetween.

Look at Jim Furyk and Moe Norman. They are probably as far apart plane wise through impact as you get. Yet, both have the RF on plane through impact. The difference will be how close to your right hip the elbow goes.

There are a few good golfers who has the right forearm slightly under plane through impact. I attribute that to a "late hit" timing.