You gotta be kidding me! I was going to post the same question. I'm seven weeks out from surgery on what the doc said was one of the worst rotator cuff tears he'd seen (fell into tank at work when grate came loose). Just finished my second week of rehab, and my cute therapist said that even though they could not repair all the tendon ends, after six weeks there's nothing (within reason) anybody could attempt that would damage the shoulder. Took the very mild-recoiling .204 Ruger (a LN rare C-Z Kevlar Varmint all that time off in a brutal winter enabled me to score; one bright spot) out on the first warm day in 4 months yesterday. A little stiff maneuvering around on the bench, but didn't feel the slightest pain or shoulder movement. Will stick with rimfire and my .20 to .22 centerfires for a while until moving up to a .243 cal. or larger just to be safe, though. I'd hazard a guess that the motion of shouldering a rifle or even shooting one off bags or bipod might even be considered a form of rehab therapy to regain range, as long as it isn't attempted before those critical few weeks after surgery. I AM NOT A DOCTOR, SO CHECK WITH A MEDICAL PROFESSIONAL FIRST. Just relating my own experience.
BTW, those little C-Z's are shooters: I used some old factory ammo with the intention of just getting on paper after scope mounting. In short order had shots almost touching on the target at what should be a 200 yd. zero. Think I'll keep it!