Quote - What exactly DOES keep Genesis from working natively in Poser? Is it just the weightmapping or a combination of things?

Any answer I give to that is likely to get me lynched, and start a new flame war, so I'll let someone else drop themselves right in it first.

 

Earlier in the thread someone asked what the difference is between the two systems, I can't speak for Poser as parametric (legacy) rigging is my lot with it.

A TriAx figure is a welded single skin mesh (grouping is not required (or needed)), with a separate skeleton, the two are held together in the same container but aren't actually connected, without WM you can actually move the bones without the mesh moving. The Weight Mapping is what binds the two parts together, and with TriAx that means you could have 10 or 11 separate WM on each bone, pushing and pulling the mesh in all three axis at once.

If you know Poser rigging then you should be able to work out the differences from that.