"Yeah, like I think you'd know a concussion if it bit you on the ass."

Considering how much damage that knife did -- yeah, Dean's not gonna bet on how much know-how this guy could possibly have.

"I mean, if that knife didn't make a dent -- "

It burns that he's got to ask the question, because four times out of ten the answer's gonna be full of bullshit, but ask it he does.

"What the hell are you?"

He'll stand up again in a second. Really he will.