[whip]

Face roll just changes the attitude of the face, I don't see how it could keep contact intact or weld the ball and face.

Ah ha! Now I understand Yoda's reference to "da bat"!

This the subject we are referring to sustaining the line of compression, if you use angled hinge it produces an uncentered motion inducing compression leakage, keeping the ball in line with it's original contact point is certainly possible! And would in effect weld the ball and face at least momentarily and not literally. I'm not sold on attitude of the face....