This is a curious one. According to this person, we all actually walk with our feet pointed slightly outwards, or point with the big toe, because we all assume that the big toe points forwards, where infact the forwards-pointing line is the outside edge of our feet, not the inside.http://www.katysays.com/yoga-toes
If I could talk to all of the yoga teachers out there about biomechanics (and someday, maybe I will!) I would say that the much more accurate and objective straight-foot marker is the outside of the foot, NOT the second toe. Toes are not attached to the foot in a fixed way, where they could be used to determine foot position.
I wonder if this is partly perhaps why my smaller toes are still a bit crabbed, because I walk with my foot pointing slightly out, which twists them. Perhaps true of every single person who has worn regular shoes, are regular shoes responsible for this?
Of course only if this website makes biomechanical sense, that is! What do others think? :-\