So, having thought about it today, I realized that I did overreact. Some of the justifications offered made sense. But I still find McGonnagal's reactions odd. Yes, a kid genius has special needs. But that doesn't mean he should be able to treat others like imbecils. It might've been just shock, but at some point it should have occured to her: I'm letting a prepubescent kid run circles around me. Even if he keeps being right, he's gonna get himself in trouble running his mouth all the time.

I know that she's supposed to be special, that most adults Harry knows DO put him in his place, but I see no reason to think that she is THAT special. She is not used to dealing with such situations (she can't even describe the one she had), and of all the teachers in the books, she's probably the one who values discipline the most.

Also, she never said: "Can you repeat what you just said? And this time, in English?" Sometimes, the situation seemed to call for a Point of View Gun from the Hitchhiker's Guide.

And there is REALLY no excuse for the temper tantrum.

And that's what a Black Hole Sue is: people act strange around her, so she might be happy.