I predict that, ceteris paribus, people who just go do things will outperform people who talk about IQ all day. :)

All day, sure- the trope of Mensa underachievers is based in reality. But people who did some very awesome things reserved some time for IQ, and I think avoiding talk of IQ in order to avoid the low-status of Mensa is as silly as talking about IQ because of the high-status of intelligence.

Based on a diversity of high functioning folks I have seen, I think single parameter models are a hopeless waste of time.

This isn't the right comparison, though- the question isn't diversity among high-functioning folks, but the difference between high-functioning and low-functioning folks. (Now, social skills, energy, and so on are important parameters that a more complete model would have- but that doesn't mean single parameter models aren't worth the time they take to populate.)