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.
related posts
The Specialization Zone
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.
Tip: Choose Your Own Squat
You have permission to do any type of squat that feels right to you, no matter what the squat Nazis say. Here's why.
500 the Hard Way
Advanced Bench Press Strategies
How to Look Freakin' Awesome
Using simple formulas, Romaniello has come up with the clearest definition of “looking awesome” yet. You have to check this out to see where you stand!