Gloria, I do not believe a Rotator Cuff tear can totally heal. I had a partial tear in mine from a fall I had back in 1995. The Orthopedic Surgeon I saw said he would rather treat the tear conservatively and with PT. Well, I did that and it still took almost a year until I could raise my arm above my shoulder height without pain.

In 2002 or so the pain in that shoulder was going from being a nagging pain to one that would keep me awake at night. I put up with the pain for another year or so, prioritizing getting Open Release Surgery done on my Carpal Tunnel on the right hand first. Finally in late 2003 the pain was so bad I finally went back to the Orthopedic Surgeon, (same one) and he wanted to operate, but I hesitated and got cortisone shots, which only helped for a very short period, after my second one I agreed to the operation.
My MRI showed I still had the same tear from 1995!! But most of my pain was now a large bone spur.
The operation went well, only three small holes in my shoulder, the Doctor "shaved" the tear away and ground out the bone spur. That was in early summer of 2004 and I am doing fine with that shoulder now over two years later.
I would recommend getting the tear repaired, regardless of if it is arthroscopic or they have to open the shoulder up for repair.

Jyes