For instance lets say I have a cube casting it’s reflection off a back wall. How can I get that reflection pass without the cube actually being there to block/cover up the reflection?
This problem becomes worse if you used textures with transparency on that cube…
I think that you only need two layers. Put the block that is to be reflected on the second layer, but do not composite it back into the shot. Check out the attached .blend. Is that what you’re looking for?
I’m not sure how to capture the reflection pass alone…