You know when someone tries to say something but they accidentally say something else even though they used all the right words they wanted to because they were sure...
Zeb was ignorant about some important facts.
Becuase of this, I think Cap has some brain damage.
Rogers has forgotten that he used to be an artist at Marvel Comics.
That's years of his life that just vanished.
Repeated blunt force trauma has taken it's toll, or a telepath has been monkeying about between his wings?
He thinks Jim Hammond killed Hitler!
Maybe it's dementia?
Despite appearances, he is quite old.