PJes, I would caution you about doing behind the neck press. I've heard many times that it is very bad for your shoulders.

I honestly dont think there is much you can do about tri involvement in shoulder pressing movements, just the same as with bench. I would just limit how hard you hit your tri's before/after you hit shoulders/chest. I know thats not what you wanted to hear, but thats all I can think of right now.

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