For shoulders, elbows and knees the problem is the center point of the joint.

The arm/elbow/knee  pivots in the center of the joint.

The wider the sleeve the stronger the strech on the outside of the bend.

To get no strech, the center point for the sleeve bend, should on the outboard edge.

The inboard sleeve cloth wil crush as cloth normally does.

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
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