"Smart" doesn't convey a lot of meaning. Smart for what purpose?
Most doctors I know are, on average, smarter than most lawyers I know in terms of pure intelligence. My husband is a doctor, and is ridiculously smart. He took one look at my LSAT prep books and could get almost perfect scores right off the bat (very irritating BTW). Just looking at his work makes my head spin. But I think lawyers tend to be more street smart, and may think more quickly on the fly. I am not sure that being more intelligent at the margins buys you much, since both lawyers and doctors tend to be very smart. And of course, this is all generalizations. I've met dumb doctors and brilliant lawyers, and vice versa.
So, nealric, your argument is that the concept of a general "intelligence" is a fraud?