He really is good, Matt is... pointing these things out to us. I read this article quite a while ago and came across it again.. When doing a lunge or squat, do NOT let your knees go past your toes. We ALL know that is TRUE... You'll hurt your knees, right? Well, read on..
Fitness Myth: Don't Let Your Knees Pass Your Toes - Your knee passes in front of your toe on every stride of every run. Good thing, too, or you’d be a terrible runner. ~Matt Fitzgerald