Also true story: if I am solving a problem and ask dude whether he knows the solution, he says yes I do, takes away my keyboard, starts googling and then refuses to return keyboard back, it is serious wtf annoying.
Also, people react different to overconfidence from woman - in my repeated experience, if woman claims she can do something technical she then starts figuring it on the fly, she will be butt of jokes. I mean, I cant figure technical stuff out on the fly in presence of some people, cause they will seriously mess into it.