Thanks fellas. It's weird that I've been training for almost 10 years and no one has raised this issue until now. It sounds like I'm not in any trouble kneeing with a dorsi-flexed foot but that I can increase my power by switching to a plantar-flexed position. If it's easy to make the change, I'll do it.
Before we wrap, I have one other question... when you're throwing a lateral knee to the outside thigh in the clinch, do you also plantar-flex? It seems more natural to dorsi-flex in that situation.
98lbweakling - You mean you can generate more power with a pointed foot? It didn't feel any more or less powerful to me. I'll have to test it.You should have your toes pointed down. The reason for this is that it sharpens your knee and exposes more bone. When your foot is flexed you tighten muscles which act as a pad on your knee.
Basically, when you point your toes, you make your knees weapons.
When you are on the balls of your feet and point your toes when you knee, it also serves to make them more graceful.
Doris flexing in front of the mirror every morning. The rest perplexes me though.