Transsexual is a modern, culture specific term.
I'm pre-op, so I don't have to ponder this stealth stuff quite yet, but I do.
If (when I am post-op) a guy asked me "did you used to be a dude?" I could reply "no" and have no guilt about saying so. I would also be quite pissed off at the question, as would any woman.
I am NOT a "dude" or a man, I NEVER was. Regardless of what anyone else thinks.
The way I see it, is that I'm a woman who has irregular genitals.