No, I reckon that like most people, he's never believed that women have penises and men have cervixes / cervices (You know what, I have absolutely no idea how to pluralise cervix!)
I reckon that just like most men, he hasn't actually put that much thought into the whole situation, because it really hasn't affected us that much as a sex.
I reckon that just like most of the center and the left he's gone along with the whole TWAW thing because it's been conflated with LGB and so therefore it's the next logical progressive thing.
And I reckon that he thought he'd get more votes from non-GCs than GCs.
What I don't reckon is that he really believes a bloke in a dress is a woman, because he's an obviously intelligent person who really seems to like a fact.
It took Mumsnet to make me TERFy. Until about this time last year I didn't know enough to have a position either way. There are a lot of people, both men and women for whom the first time they really thought about this stuff was the whole Scottish Prisons thing.
Do I know whether Starmer is one of these people? No.
But I'll be voting labour either way, because while this issue is hugely important to me (I may be male but I have teenage daughters), I also have a pressing need to eat, and house myself, and stay warm.
So I'll be voting for whoever can get the Conservatives out. And then I'll continue doing whatever I can to move the needle with whoever is in government.