[nevermind]

"preselected Downstroke Clubshaft Plane" simply means the clubshaft on which the player wants to utilise on the downstroke.

If you shift during the Downstroke, which plane is the preselected plane? Or, is there only ever a preselected Downstroke Clubshaft Plane in a zero shift Downstroke?

If the Turned Shoulder Plane is the angle from the the plane line up to the rear shoulder at the end of the Backstroke(no matter what type of Shoulder Turn took place), how can the rear shoulder move downplane at start down on anything but the Turned Shoulder Plane?

The "rear shoulder" and "rear forearm" can be in a straight line (with the clubshaft) if one bends the right ("rear) elbow in towards the right hip. It will appear in a straight line if viewed from a "down-the-line" perspective.

I can't picture this comdpa Are there any photos or diagrams that could clear this up for me?

Another question. For how long should the rear shoulder move downplane? I see many down the line sequences showing the rear shoulder moving above plane before impact, but few with it remaining on plane to both arms straight. What is ideal?