Would puncturing the bottom radiator hose not really leak until the pump starts up? Like it would be a slight drip that could be overlooked/unnoticed and a full stream once on and running. Hopefully after driving away a few miles.
I dont want to crawl under a car. Puncturing the radiator is a way to quickly immobilize a vehicle in a way that requires substantial repair. All of these "sugar in th gas tank!" "unscrew their tire stems!" ideas sound fun but they take time and thus make them fantasies. I want something quick and obvious that succeeds.