Turning the feet out is supposed to accentuate hitting the outer quads from what I've always been taught. I've done all the different stances before, but I found out my foot position has been affecting how much each exercise hits my quads--specifically how the foot rotates from side to side. After figuring out that because I tend to walk on the outside edge of my feet, I have to make sure I rotate my foot in enough so that it is flat and stays flat during the exercise. This alone has started to help me build my quads. Since figuring that out, I'm going back to a wider stance, feet pointed out, and going down to parallel. I'll go ass to the grass on light weight with that stance.