An update to my May 9, 2011 post on this topic. A friend of mine who has different knee issues recently recommended aqua jogging as something that really strengthens the leg muscles w/o the pounding pain that comes from regular walking or running. I tried it in the pool (it requires you wearing a flotation belt). For the first several minutes I had a problem because periodically a tendon on the lateral side of my left knee would would catch when riding over the bone spur I described in my earlier posting. That's a very uncomfortable feeling, and I thought I'd have to stop the aqua jogging.
Then the "twanging" went away! I don't know whether I simply wore down the bond spur over time and repeated abration of the tendon against the spur or whether something else happened. I suspect the former. But since that day, I have had no real instances of the tendon being "caught" by the bone spur. I periodically still feel the tendon rub over the spur, but it does not catch the way it did earlier. My my orthopedic surgeon apparently was right about NOT going in to surgically remove such spurs (as a general rule).
I've only done aqua jogging once or twice since the first time, but I have never had the major bone spur issue return. Se at least this is a "positive" development in my growing history of knee problems.