Strange... I remember back when we first got TIR, and everyone was stoked because BR5 could complete all of it's internal reflections. This technique is definitely a step backwards, but I have seen some awesome images as a result. Still, to complete internal reflection, space as well as diffusion needs to be represented... Look at anything glass around you, and you'll see what I mean. Two glasses side-by-side would have to have TOTALLY DIFFERENT reflection maps to work with this method, and be true to internal reflection, due to parallactic displacement...