Another Read The Whole Thing essay. This one from American Transman, detailing a case which until I read it, I thought was physically impossible.
Well Reality doesn't care what we think. It takes only one ugly little fact to slay the most elegant theory.
So please read Part 4 Male Gender Identity in an Individual With Complete Androgen Insensitivity Syndrome | American Trans Man for a really good analysis of a rare situation, and some postulated modifications to existing theory to account for it. A really good piece of work.