His was a universal pronoun for almost 200 years until the women's lib movement of the 1960s. Know what? A lot of dumb things happened in the 1960s. It's 2010. Let's not spend our time arguing over pronouns.
Really, I think a more realistic solution is to just alternate between using 'he' and 'she' in your work; "they" grates on my ears when it's used in the singular, personally.
I learn all my etymology from Dinosaur Comics, http://www.qwantz.com/index.php?comic=551 :)