**"1) if you performed one SubD, would the topology still be ideal for Poser?"**

IMHO Catmull clark subdivision,on the fly,would have been a great addition to poser9/Pro and not just for any Genesis compatibility.
working,posing,animating with a system friendly low res
meshes and switching on SubD only at render time is nice workflow.

Attached are two identical copies of the DAZ Mike 3 reduced resolution in Maxon Cinema4D click loaded  directly from my runtime Via the Interposer® plugin.

The left copy has a hyper nurbs modifier with the display division set to one and the render division set to 2
I could set the division as high as my hardware will handle and still have all the morphs functional ( as this African+smile morph demonstrates.)

I read about Snarlys SubD script... nice effort but SM needs to implement a proper CC SubD feature in poser if it Seriously wants to move forward in Figure rig handling tech IMHO.

Cheers

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