There are different stages of an RC tear.....I, II, IIIa and IIIB, and IV. Surgery isnt indicated for I, isnt indicated for II and III unless you already failed physical therapy. It is indicated outright for stage IV. If you are already seeing a doc, then do what he says. If you dont trust him or believe him, then get a second opinion from someone who doesnt know him.
The reason it doesnt hurt for bench press is cuz you arent using your supraspinatus, infraspinatus, teres minor, or subscapularis except for stabilizing your motion. Dumbbell bench will hurt alot more than flat bench. Those are the muscles of your RC by the way.
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