Any idea how many of them? I know of a few, the kind that make the newspapers, but I have no idea if it happens privately or not. I don't know any personally.
I had the impression that it was pretty rare. Nothing wrong with it; it appears to work perfectly well. But nonetheless I would have expected it to not occur all that often, since the transition is so much trouble and so important to their well-being.
True but the person getting treatment doesn't become a man. She's still a woman, no? The moustaches are usually reminiscent of faint early teenager 'staches and not gruff looking.
You're correct that they don't become a man. They always were a man, and are now undergoing treatments to bring their bodies in line with their gender.
Testosterone is testosterone, and it makes facial hair regardless of your genitals. I know several trans men who have significantly better beards than I have. They don't need beards to be men, though I think many appreciate the visible confirmation that their bodies now match what they understand themselves to be.