I asked this in the BB forum, and I think Chris brought up a good point that "your exercise specific warm-up should be more than sufficient to cover the rotator cuff. One thing you may be doing is actually fatiguing those muscles which are already weaker than the larger muscles of the shoulder thus leaving them more prone to minor or significant injury."
And so to continue the discussion, what do you guys think? Should all rotator-specific exercises be done after workouts? Or even on a different day altogether? Is there any use to pre-workout rotator work? I have rather vulnerable rotator cuffs, and so I want to make sure I'm doing everything I can to keep them from getting injured.