'This guy knows what I'm talking about

An expression used to diffuse responsibility for an unpopular statement made in a public setting. Typically used to imply complicity or collusion on the part of an unwilling stranger.
You: I mean, really, who hasn't made out with a rundown fat chick in a moment of drunken desperation.

Crowd: *silence*

You: *smile and point to a random guy in the crowd* This guy knows what I'm talking about.'

Omg, that makes complete sense! *Has an Urban Dictionary relief moment"

phone: why don’t you go to sleep tommy it’s 2 in the morning?
tommy:why don’t you die you dumbazz