Is daily use of the rocket arm useless or is it helping me with something. Also your suppose to do the excersises slowly but for a pitcher you want fast muscles is that a problem.
Slow and steady, Ace! The type of excercises you do with that equipment are designed to build the small muscles around the shoulder cap, which protects the shoulder joint from the stresses of throwing, and increase the elasticity of the upper back and arm muscles, and they seem to have helped my son.
Remember to work your core (abdomenals and low back) with crunches and pushups, and throw every day. I would suggest getting together with a pitching coach if you haven’t already, to develop an off-season work-out program specifically designed for you and what you want to improve.