I certainly wouldn't blow the floats, I'd be quite busy enough trying to fire the flares, pick a site, call Mayday and get in a bit of quiet screaming, "Why me, God, why me?!"
They were called Schermuly flares, by the way. Bright light on a parachute. Bang one when the donk goes, find your field, pop the next at 1000ft or so. Not cheap to fit and the flares go out of date after a time. Inadvertent firing of flares by RadHaz was a danger, particularly in a hangar!
They were rendered uneccessary if you had two landing lights, one of them steerable. Phew!