" and every so often a breast will head for the waist or try to implode into the chest. " I've noticed something like this happening with Walk Designer motions. Because the script figures instantaneous acceleration, an unnatural "hitch" in the real motion can cause an extreme acceleration that would be physically impossible in real life, because the original "hitch" is also physically impossible. I might try a median filter to eliminate extreme values. Of course you could set the Max and Min on the morph dial to keep things under control.

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