When I attempt to Simplify a mesh with 245M tris, a message I’ve not seen before pops up, “Simplification, orthographic projection, smoothing, and closing of holes works just with a selection of triangles.” If I click Okay, the resulting mesh has about half the parts, but the same number of tris. In Sweet or Solid view mode, there are clearly triangles present. I have an RR automatically generated. I also tried Select All, but nada. What gives?
Solved. Evidently, after Texturing RC defaults to picking a part, not all parts, so you now need to click Deselect to have all parts selected. No idea what purpose that serves.