"Yes, provided that the geometry is embedded, renaming the .pp2 extension to .obj will create an obj"

I'd say that strictly speaking, you're not creating an .obj. It's more a matter of luck that some applications ignore the Poser code and read the valid vertex and face entities. Vue apparently doesn't (for the one file I tried) and DS3 appears to read it but I couldn't see the object as anything but a tiny cube and then only when selected. OTOH, I could see the same file after saving it as an .obj out of UVMapper. That may have had to do with scaling or something, I didn't play with it very long. I'm assuming that for the apps where it does work, it would work equally well with a .hr2 with embedded geometry. The moral being, it's not a valid .obj file that you can just use in anything. And pity the person who renamed their prop, modified & saved it, expecting to rename it back and get a valid .pp2 :-)

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken