When a person or an article tells me, what is the "correct" and/or "incorrect" way to position my hat, I know I'm reading something or listening to someone that shouldn't be trusted.
I couldn't agree more. I don't believe there are "correct" or "incorrect" ways to dress, so long as one enjoys what he's doing. To clarify, I linked to that page more for a very general way for people who are interested to try different angles and see how they look. I don't mean to be prescriptive in any way. And you make a great point about a hat's practical use. I often readjust my fedora depending on the angle of wind, rain, sun, etc. In general, however, I've found that a side and back tilt looks best to me.