This is concerning the walking a straight line while blindfolded, If your (left/right) stride is just shorter or longer than the other side, wouldn't you start arcing to one side or the other over time?
I don't think it's a matter of orientation. I believe it's from having a dominant foot, like we have a dominant hand. It stretches a wee bit farther. I think a blind folded person could walk a straight line, with a audio beacon.