gone plaid
Reached a state of babbling incoherence, rambling random, absurd gibberish. Origin: Spaceballs
By that point, he had long since gone plaid, and had no idea what he was trying to say.
gone to plaid
When something moves entirely too fast (reference from Spaceballs) especially in the case of a relationship.
Joe - Hey did you hear Ken and Sue are engaged already?
Mike - But they just met last week!
Joe - I know, they've totally gone to plaid.
Mike - But they just met last week!
Joe - I know, they've totally gone to plaid.