Gotta say I'm also curious on this question.
I can ride pretty much any marked run, small hills or big mountain, but I'm going for my Level 2 instructor cert. here in Canada next weekend and I'm nervous about maintaining "proper" form during the course.
And yes, I too see guys riding with "technically" improper form, yet flying around the slopes.
I'm sure many on here don't necessarily respect the standards from AASI or CASI, but they are the ones who certify people to teach.