Some 20 years ago there was a story about a guy who was opening a bank account. The bank sent the contract, the guy ameneded it with things like "you will give le unlimited credit that I do not need to repay" (if my memory serves me right).

He signed, sent both copies, got his bank signed copy back

Went yo the bank, the bank sued him, he won (the judge told the bank that when you play dirty games you sometimes loose) and they ultimately settled.