I've heard Coach say that it's ok to work on dislocates for shoulder mobility even before getting to PE5 and PE6.
That leads me to wonder whether undergrip dislocates are a progression from overgrip dislocates that should only be practiced once the overgrip exercise is mastered. Or are they separate enough that I can do some undergrip work from time to time before I'm able to do mastery with the overgrip.
Just to be clear, I'm talking about using dislocates as a mobility exercise APART from the regular HS practice, which I'm doing according to the rules in the program.