Great question. I never thought about this before, but I think it requires more balance, so being on the edge, between things and therefore represents the place between two different dimensions, so kind of not going either way. Eventually, from a psychological perspective, a person does have to go one way or the other, and that can be threatening, as the person may unconsciously fear that he lose himself, so toe walking would be a good compensatory mechanism, somewhat akin to stimming. It should be mentioned that when I was pregnant with my second child, a single mother at age 40, and a big step for me to dare to dare to have that child, I could not get enough of being physically on the edge of things, such as sleeping on the very edge of the bed with part of my body even hanging off. It was extremely comforting to me. Have never done it before or since and did not do it with my first pregnancy when I was married. Psychologically, though, in terms of thinking, I am very interested in edges, and am also attracted to bad boys and edgy situations in general, though not as much any more. I kind of miss it, actually.