I suppose the point is you wouldn't know. If a MTF transitioned to a point at which you couldnt tell that they were ever a man then you would just naturally accept them in everyday society
No TIMs pass. You can always tell. Usually it's the Adam's Apple, deep set eyes, heavy brow bone, wide shoulders, lack of hips, massive hands and feet and taller than average height.
But for those vanishingly rare TIMs who do pass physically, the male entitlement always gives them away in the end. If you were born and socialised as a male, you will never ever pass as female. End of.