The problem with rotator cuff tears is no one is ever frigging specific about what muscle that is torn.... Each muscle has a very different function it shouldn't be generalized together.
Rotator cuff tears can also coincide with other shoulder injuries that need to be addressed as well.
As for working out, it depends on your fitness level. Knee stabilization is pretty f'ing vital. I see riders all the time who are at high risk of doing some permanent damage to their knee. ALl of it is preventable