Sorry if I get a little irreverant at times. : But seriously try it sometime. Do this on an easy intermediate run, have a spotter with you and try to ski and turn down the hill while blindfolded. Boy, this will tell ya right now if you are in correct balance. I really didn't think I was back at all when skiing. That is until I sat on my butt about 3 times in 2 turns. Really a great drill to point out correct balance. You can't fake it at all when blind you're either balanced laterally and fore aft or youre on your butt/side etc.
Sorry to chime in so late and out of order, but, as a bystander and potential student, it is all of these conflicting techniques throughout my life (30 years plus of skiing) that have made me lose interest in being instructed. Half the time I can't tell who is agreeing with whom, even in this fight. I think without head to head videos that most non-instructors' just don't get what the heck you are saying to each other.