Stringtheory has come up with a method to use a soft body attach proxy for a figure that saves significant calculation time in soft body physics. Turn off collide with other objects for the character (M4, V4, or whatever) and use a vertex envelope soft body attached to the bones to proxy for the moving person. Early stages, but might have potential.   There is a thread on the Daz forum, but I know people here have also experimented with softbody physics.