this is interesting. i always had a gut feeling that kipping pullups were a huge factor in my shoulder issues, but with my limited kinesio knowledge, i figured that it had to be pressing motions causing the troubles.
i will admit that, when i was tired, i had many instances of letting my connective tissue and not so much my muscles take the brunt of the force in the bottom of the kipping pullup.
at a KB seminar several years ago, i asked steve maxwell what he thought about crossfit. he only really made 2 quick statements: he made a brief comment about the politics of it being as troublesome as the politics of the kettlebell community, and then he put a little more weight on his second statement about a lot of good athletes simultaneously ruining their shoulders and, subsequently, their potential. he was mainly referring to the kipping pullups. at the time crossfit was new and shiny to me, so i jumped in head first anyways.
that tidbit on biceps and curls is interesting. occasionally when i'm doing some rotator cuff work with dumbells at home, i'll do some curls because i feel a tight stretch in some tendon running through my anterior delt and running up my neck a bit. i don't like to stress it too much, but it feels nice to open up. would anybody recommend bicep curls as an actual shoulder stabilizing drill?