Polish - I appreciate your comments, but I'll offer my own views as well.
To be fair I never arch my back, it stays neutral, personal preference.
core - I don't know, It didn't feel to bad, but we could always use more core strength I suppose.
knees - I do that ever since I squatted, wether the weight is heavy or light. It doesn't bother me, and every person I've seen who squats in the same style of squat does the same thing judging from the Ironmind tapes. Especially on front squats.
I don't bother trying to push my knees out, that's just another distraction I can do without, I just let me body do it naturally.
I actually push my knees outwards slightly on the way down, unlocks the hips for me, so you would naturally expect them to spring back inwards to their normal path on the way back up.
Watch the clip carefully and you'll see I push my legs outwards on the way down an dthen on the way up they pop back into their normal path
Like I keep saying, Mel Siff says, it's normal for the legs to do that when moving heavy weights. And Mel Siff knows a lot more than any of us
The weight is a PR, so it has to be heavy and near my limits. I'm supposed to pushing myself hard right at the end of the loading cycle. The human body isn't a machine and the squat is a 3 dimensional movement, so you can't expect perfectly strict planes of motion. Lifting at 70% and under I could get close to ideal, but that wouldn't be a PR though
