I honestly don't care enough to try to change the medical definition of the disorder.
My estimation though, is just because people do crazy ish, does not make it a valid thing. In the same way we can argue day and night whether or not there is or isn't a soul. We can also argue whether gender is determined by physical characteristics, socialization or some sort of 'mind-gender.'
I don't know, and I don't science has much empirical evidene to prove the point either way.
What I do know is there are people who also think they are leopards or birds. They are in insane asylums.
Or closer to home, if I went to the Doctor and said, I feel I am meant to be more masculine, a veritable werewolf of a man...give me male hormones! They would discredit my desire as not socially acceptable. But if I said, I WANT BITCH TITS, I WANT TO BE A FEMALE, GIVE ME A VAG, LOWER MY TESTERONE! Obama would give me a damn job!
I think that we should focus on confronting that hypocrisy, rather than debating the veracity of transexuality or not.
For me, all that matters is...was he/she the most qualified candidate? Probably not, her oddity was to get Obama political points from the left.
In this case I disagree with it.