The variation of the band pull-apart method has you doing regular reps, but slower than usual. This is more for muscle-building than improving weak spots or improving the role of the back in the bench press.
Depending on your objective, you can vary the approach. It's practically impossible to overdo pull-aparts, so use them often.
If you want to build huge muscles, you must continually challenge them by placing a greater demand upon them. If you stick with the same stress level month after month, you'll quickly reach a point where your body is used to the stress and won't need to adapt (i.e. grow) anymore.
Dr. Ken Kinakin, much like Dr. Mike Leahy, knows your pain. In fact, he's made a living off of it. The doc is one of the best in the world at devising training protocols to help make you injury-proof. Yeah, he likes bodybuilding and powerlifting routines, too, but when it comes to figuring out how to fix what ails ya', he's one of the best.