missy did not say “one of these is wrong” but “one of these is a lie”.

why would she say that the doctor having been a girl is bad or a joke, since she also has changed her gender and clearly enjoys herself in her current form? what would be her motivation?

I liked the scene, because it opens up the possibility that the doctor already had a female form before s_he started traveling. I’m also not quite sure if the analogy between transness and changing your gender through regeneration works, because there are so many things that are completely different.

about the second joke: the doctor says “snake nest in a dress”, not “man in a dress”.

I’m trans myself, so I am generally quite sensitive about transphobic jokes, but did not think there were any in this episode. just my thoughts.

Thank you (I mishead the second line) :-).

I meant “wrong” as in the sense of “a lie” (sorry if that wasn’t clear). I don’t know (with Moffat’s previous negativity about the idea of the Doctor being played by a woman) if it’s deliberately opening up the possibility, but it’s definitely something that could be used later to justify a trans/genderfluid Doctor (although whether it will be is another matter). 

- C