The use of a narrative to describe a complex situation is, IMHO, a cop-out. You have simply replaced one limited encoding with a linguistic one subject to language, cultural, and social complexity. How is " 1=male, 0=female, and nothing when unknown, in order to avoid locale dependencies." better than M, F, B, Q for male, female, bi and queer? Its different, but I don't see its better. Of course, queer may be socially unacceptable in some societies, so you still have a mapping problem.