The Time Lords, if nothing else, had a very complete understanding of gender. As a race that couldn't guarantee that the next day they wouldn't have different bits, they became patently adept at reassignment and gender role ambiguity.
No Time Lord would address another first by a pronoun. One could never tell, and besides, it was rude. So it was always 'your honor', 'friend', or even just 'hey you' until a name and gender were given. "The Monk, male" or "Rassilon, female" were standard introductions. A person's face, the curves of their body, the hair on their chest- it meant nothing, except to the person who wore the skin.
Of course, there were those whose gender truly did change with their bodies, and those who reminisced of the previous regenerations in the way they dressed or held themselves.
The wide spectrum and the swing and shift of gender was one reason for the use of the looms instead of natural reproduction- parents did not always fit together the way nature required them to in order to make a child. Still, ask one of the few who decided to undergo the swollen breasts and pelvic pains, and you'd find it was no great loss for them.
There were many things wrong with the Time Lords. Arrogant, manipulative, often cruel and demanding, but on the topic of gender, no one understood better that the shape you hold and the person you are do not define you. And in that, at least, they were completely right.
A/N: This story (analysis? character study?) begged to be written. So I wrote it. Hope you liked it. :D