I don't really knnnooooow... I think I always walked heel-toe, but one of the people I knew in middle school walked on his toes and I was impressed because it looked like how a dog walks, so I started imitating him. (Doing just toes.) I stopped after a while. Then later I gave up shoes altogether and now I walk toe-heel, because it comes natural when you have no shoes on, and that's how you're really s'posed to walk, you know. (Better for your knees and hips.) Everyone just walks heel-toe because the heels of shoes are all slightly thicker than the toe, so it hits the ground first even if you put your foot down flat or slightly forward.
I guess I'm kind of an expert or something. XD;
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"You gotta keep making decisions, even if they're wrong decisions, you know. If you don't make decisions, you're stuffed."
- Joe Simpson