Can you set up joint controlled geometry switching in Poser? I'm not clear on how this would work. You might need to re-optimize the rigging (weight maps/falloff zones) for each posed version of the figure and for the figure's conforming clothes.

When you create a JCM, you are making a corrected model of the posed figure. I'm not sure what the advantage of geometry switching would be. Would there be a change in the vertex count? What would this mean for FBMs? There might be something useful in this method, but I think there would be a lot of frustration on the way to finding it.

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