Well.....I'm near the end of PT and in the middle of rehab from my shoulder surgery. I had a torn Labrum, a very large tear in the rotator cuff tendon (2 1/2 in. wide tear) torn biceps tendon, detached supraspinatus, torn infraspinatus, and small tear in the teres minor. I did the damage 9 yrs ago and waited this long. On one hand, 9 yrs ago surgical techniques wouldn't have been this good. Otoh...perhaps the damage got worse in the 9 yrs. But I digress....
My advice is be religous in the PT...make it your job. The doctor will do his job, you do your job and the therapist will get you back all or most of the range of motion. My tear was about as large as they can repair...so it's 6 months until I can do anything like make a 'full' swing. I can pitch now but I don't....cuz I know me and I'd be hitting driver the second time I went to pitch. In my case, I may loose some range of motion because the tendon flexiblity was used to cover the tear, you may not lose any at all. But again, if you do what the therapist asks of you...you'll get all you can out of the operation. I am for the most part pain free now, as opposed to waking up every hour at night pre operation from shoulder pain....I do have some arthritis in the A/C joint that causes some discomfort (that was dislocated along with the other stuff). But I can deal with that by using ice. After the operation, I was in a sling for 9 days, you will suffer some atrophy...probably more than you think
.... don't rush anything in the healing process, don't plan on putting up any ceiling fans for 3 months or so...just follow orders, you'll be fine as you can be. EVERYONE I know that has had shoulder surgery in the last 10 yrs and had a bad experience......DIDN'T do what they were supposed to do after the operation. I recoginize that I don't personally know all people who have had shoulder operations and I'm sure there are some doctors that don't do a good job. Yours looks like a great doctor, you'll have a sucessful operation. Good Luck!