Probably because a few days at sea later... he'll pop his emergency beacon and the Coast Guard will spend a bunch of time and resources plucking him out of the

Probably because a few days at sea later... he'll pop his emergency beacon and the Coast Guard will spend a bunch of time and resources plucking him out of the water. With ocean currents, winds, etc., it seems vastly unlikely his contraption would have traveled any distance the ocean didn't allow anyway.