nonradio,
I'm sorry if it sounds elitist, but I've never yet met a pilot who didn't at least appear to have an above average IQ. I'm an ex-occupational psychologist; I've worked with the "general public". Do you have any idea at all how "low" the "average" is? "Average" people wouldn't usually pass the PPL ground exams, or cope with radio work while flying and navigating, or anything like that. "Thick" is a relative term. Elitist or not, I strongly suspect virtually all pilots have above average IQs. But someone must have researched this? Anyone know?