On what rational evidential basis is a man who is proposing to undergo gender reassignment a woman?
On the basis that 'woman' has two meanings, and whilst one of those is immutable and determined at birth - the one you're relying on - the other is malleable and an artefact of the individual's interaction with society.
Because he says he is a woman? You're just going to take his word for it are you?
No, because she says she's a woman; and, yes, I'm going to take her word for it. And until and unless there's a strong, specific reason that biological sex is important - and here are circumstances where that's the case - what sex someone is should be irrelevant.
If someone's say so is enough for you then I assume over on the Searching for God thread you'll just be taking Alan's word for it that he has had several encounters with God through prayer. If not, why not?
Because, whilst women have been shown to exist, so has femininity. Femininity, though, varies by culture, and is therefore not an inherent trait, but a social one, and therefore isn't intrinsically tied to biological sex. Gods, meanwhile, have not been shown to exist.
O.