I remember when I was growing up that we had a doctor living in town (Dr. Robinson) who was a surgeon and specialized in removing brain tumors. He also LOVED classic cars and owned many while he was alive, but dared not work on the messier bits, since it was always so difficult, afterwards, to get his hands clean and sterilized before surgery.
He had a son (Lee, now a System Engineer for SUN Microsystems) who turned into one of the best engine builders I know and did all the engine rebuilds for his dad's cars. When he's not solving customer problems for SUN, he's still building Street Rods and classics.
Guess that's how people tend toward specialized talents.