Re: let me guess
The whole "doctor" thing is way overblown, mostly by overblown people. [...] but no one I know of refers to themselves as "doctor"
Methinks you miss the point. People don't call themselves Doctor (unless perhaps in a CV situation), but it's really useful for addressing a stranger in formal or semi-formal correspondence. Works equally for both sexes where there's any uncertainty, and is unlikely to offend even if it's not technically correct.