There's this phenomenon where two people are talking, and one of them offhandedly mentions some innocuous fact, and the other one has to stop them and have them explain both the fact, and what they expected their interlocutor to infer from the fact. When this happens once, it's usually just a matter of one happening to have some domain-specific knowledge that the other happened to not have, a coincidence that could just as easily have gone the other way.

When it happens multiple times with multiple topics, with both people in the same roles, the one who keeps having to ask for explanations begins to suspect that maybe it is not a coincidence, that maybe the other person just knows more stuff, full stop.

Standing at 130, you typically spend a lot more time talking down to 110 than being talked down to from 150, so it's an unusual feeling of helplessness. You want to cry out, "You know, I'm usually on the other side of this conversation!"

"I know," they say.