A reimagining of the historical colloquialism 'Ass over tit' whereby a person suffers some sort of accident, executes an elaborate fall and lands heavily on the ground. Can be used to describe an actual physical situation, or an unsuccessful process.
The flammin' dog ran in front of me as I was coming out of the kitchen with my hands full and I went Cunt over Cleavage.
The project manager is a useless as tits on a bull, and the whole operation has gone Cunt over Cleavage.