OK, I haven't taken the time to read the whole thread (I'm just grabbing a bite to eat, then it's back into the attic spaces running cable), but my experience is this:  Sometimes, increasing irradiance cache can reduce the flicker to the point where it's no longer an issue.

     Otherwise, you can try rendering out the series of frames three times, and compositing/averaging the three renders for each frame.  Make each render an object/layer of 33% opacity (well, the bottom layer would be 100% opaque).  This smooths out the random seed effect considerably.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5