I am a basketball coach and am worried about completely blowing the acl out if it is not treated properly. Always get a second opinion. If it is indeed a partil tear, your doc is right, let it heal. Definitely work on strengthening the knee. There is evidence that training can reduce the risk, but it can't prevent all injuries.
Some people believe that yoga stretching is more extreme then benificial.
Proper stretching should not increase risk. I have heard yes's and no's. There is a significantly higher risk of arthritis after this surgery. I run about 3.5 miles a day and I was wondering how much damage I'm doing to my knees. Just wear good well-cushioned shoes, and cahange the often.