I've been doing overhad squats now for over 6 months. I'm gradually working up to higher weight and I really, really like them. I can definitely feel the difference in my core -- things have gotten a lot tighter.
The question I have is whether your knees should be allowed to move forward past your toes during an OH squat. I know the "standard" recommendation on back squats is to keep the knees behind the toes (is this to prevent back or knee problems??) I can do this relatively good with back squats, but it's a killer with OH squats, I think because of the shift in center of gravity.
So should I back off heavier weights on OH squats and try to keep my kness back? Or does it really matter? I keep seeing pics of Olympic lifters doing snatches, and often I see their knees very forward.