ShawnDriscoll, "Most retopology I ever do is for creating a lo-res base mesh from a detailed object that I've baked a normal map from to then apply onto the retopo mesh."

Yes that is the normal way to work with zBrush for example but this is different.

You can make a dress in Marvelous Designer in 10 min with first class UV maps that can be used in Poser as dynamic cloth directly. However the triangular mesh is unsuitable as a base for conforming clothing. It must be retopoligized, so the planned workflow is this,

1. Make cloth in MD
2. Do texturing in Blacksmith or Bodypaint or whatever, after where you have one piece of Dynamic Clothing

then,

3. Retop keeping all material zones intact.
4. Make new UV map (from the material zones)
5. Minor tweaking to make the texture fit the new map

Voila! You can now distribute your piece in both Dynamic and Conforming format.

 Edit: You must think outside the box! :)