I'm curious how you would solve the GI problem with Reyes; note that doing something like like photon mapping or radiosity isn't Reyes itself.

Photon mapping. I've never gotten radiosity debugged properly. I tend to like Reyes as something that works for NURB tersellation for me than the triangle interpolation thing. It could be that I'm a lazy programmer that has trouble with textures using classic z-buff techniques.