Since dual IR emitter remotes still have both emitters in the front, you still need to aim them. However, remotes with strong IR emitter(s) can "bounce" the signal around the room and hit equipment completely out of the line of sight.

But just because a remote has 2 emitters does not guarantee that they're strong. I've seen single emitter remotes that were much stronger than some dual ones. And don't forget the remotes that have *four* emitters! :-)

Incidentally, the only traditional remote I'm aware of to have an emitter anywhere other than the direct front is the UEI Mosaic (One For All URC-9960), which had two that aimed out the side.