Yea its tough because not everyone has access to imaging easily or has seen a physician. And even if they have its extremely...i mean EXTREMELY uncommon to have an isolate supra strain that would subsequently benefit from isolated rehab although i have seen it.
I just cringe with people " work there rotator cuff" which certain exercises. The one that makes me cringe the absolute most is humerus abducted to 90 degrees and elbow flexed 90 degrees and rotating up in half circles up and down. That is TERRIBLE! it closes your AC joint/humeral head distance and most people have entheso/osteo phytes projecting right next to the myotendinos junction and it just can rub your tendon back and forth causing small tears.
The issue i have is these "gurus" on youtube etc have no clue. So that exercise would be fine for a 14 yr old boy with no prior issues but for bodybuilders with years under the weights they will have AC joint arthrosis and already have tendinosis so now there is a big issue with doing those movements. In order to work supra you have to do it at the lower ranges of motion, like maybe laying on a 45 degree angle on a bench and doin laterals like that or taking a few steps away from the cables and doing side laterals but not going up all the way.
Ok but now im rambling. Just FYI.... most shoulder pain isnt cuff pathology. Minor pain is often biceps tendon issues and bursitis. Clicking is commonly labral with you arent gonna rehab your way through.
If you are trying to work your cuff then you need to focus on the negative portion VERY slowly....like 4-5 seconds down. Thats what will help your tendons heal over time..