Here is a hard one. hang yourself on the bar or rope using one hand and start to shrug bringing your body up and down as you hang on the rope or bar. Alternate arms and check yourself. I had a hard time completing 60 for each hand and felt good I discovered a weakness so easily. This will free up your shoulder potential as I see it but don’t push too hard. Be smart. Another good point is to notice how the weakness spreads as you find a new point in yourself. Notice the path or leak in yourself and make use of this knowledge.