From what I've seen, there's a "golden" IQ point that makes you intellectually capable of doing or understanding most things but not so lofty that things like interpersonal relationships are inconsequential. I think they say that it's around 130 IQ, which is, I guess, the range of most people in high leadership positions in the private sector.

Regarding the anecdote of your high-school friend: Yes, I'll bet most of us known people like this. However it doesn't seem to affect the statistical results. In studies with large groups of people over long periods of time, there is a correlation between IQ and economic position.

As to your point about intelligence being genetic, I agree totally. All my children are as smart as their father

Lol, I sure hope it isn't! I'd feel bad for my son XD