Poser 4, does render darker(black) polygons with inverted normals (at least, mine does, oldie from MetaCreations) but it is OK if you think otherwise, lol :D To tell you the truth, I never had polygon created out of 2 vertices, since I started modeling, by modeler itself, looks like Poser might be interpolating numbers and rounding them up so it looks like it has only 2 of them...dunno. Since I subdivide and un-subdivide OBJ models almost every day for my needs i would think that it make some sence, otherwise I would not do it, assuming all this time that rendering engine is Bryce 5 which I exclusively work with :D