Hm. It sounds to be pretty effective. Rotator cuff injuries can be quite painful. I would have advised you to do either pushups and pullus to minimize injury, but with the injuries you described, it would not be wise to try those exercises. My friends and I have a belief that working against your own weight (pushups, pullups, lunges, etc.) is probably the safest way to exercise. But some doubt that it is the most effective method of exercise. I would say that very very light stretching would be your best bet. From your past questions, it appears as if you need to go extremely light in the beginning. In your case, I would walk short distances for a while before even attempting to jog. Jogging and running are also hard on the knees. I used to be a pretty good cross country runner and have heard that many long distance runner’s careers were shortened by knee injuries. The years of pounding take their toll and eventually the joints are damaged; even if one is using the proper technique. I have heard good things about isometrics and passive stretching. It sounds as if that would be beneficial in your case. Remember to go very very light. Don’t rush anything. Safe, minimal exercise would be much better than risking any further injury.