Or bootlegging.
Nobody's made a point of it, but can you use Nero to burn DIFFERENT CD's at the same time? Or any other CD burning software? I've not tried Nero with two drives, and I've never run into a need to burn two discs at once anyway. If you can't burn different discs, can you just use two different burning apps at the same time? Or will they interfere with each other?
If you can't burn different things at the same time, that'd kind of kill the "image backup" theory, unless he wants multiple copies of his backups.