Quote - I don't know Lightwave, but in Blender that would be about the only way to go about it.  Normally if you're going to have two versions you'd do the lores one first, map it, then subdivide and sculpt for the HR version.

Well that's what I've typically done in LW when I've worked on figures to be used in LW. And it works just fine to take a low res UV mapped figure and subdivide it, or even add polygons as long as they don't touch the seams of the UV map, and any textures still work well.
But this is for a figure that has to be able to work and render properly in Poser, so I'm not so sure if that's the best way to go about it in this case, or if there's a better way to do it.

Truth is, I've simply never tried it before. For the stuff I've made for my own use, I've had only one version, either hi res or lo res, and never had to think about how to have two versions of the same  figure, sharing the same UVs.