Maybe the fact that women make the two locations "identical" means they get to learn both places, whereas men don't, since they simply bore a hole to the place.

That would explain RJ's quote about Nynaeve and Lan, but it would still mean that Sanderson's "trick" in tGS is a contradiction of the earlier books.

As for RJ's quote about Rahvin, the question put to RJ was why Rahvin was still lounging around in his throne room when he had felt Rand's gateway triggering his traps in the city below.

RJ explicitly said that although Rahvin knew Rand had arrived in the city, he did not expect Rand to know that you can Travel short distances even if you don't know a location. Hence Rahvin's surprise when Rand rocked up in his sitting room.

So to me that means that while Rahvin knew Rand had Traveled into the city, he knew that this does not make you know a location, and that he did not expect Rand to know about the "short" gateway ability in unknown locations.