Why would they not be safe? Use common sense, don't jolt the movement and don't try and force the joint too far, same with any other stretch and I can't see why there would be a problem.
i use that movment but only up and over head and behind back! I have an injured left shoulder which admittedly is in the best shape its been for a long time however it still bugs me! Like today when iv woken up with slight pain in it!
Not like that. Asking for trouble. Stretching should be done slow. There are alot better ways and safer ways to work your shoulders. Try looking at ---- "The Seven Minute Rotator Cuff Solution" Dont be a ******.