I was taught in the military that in an emergency situation, your training will automatically kick in and you will do what needs to be done without having to think about what needs to be done. I go out to a lake and over turn my canoe to learn where the point of no return is, to test my pfd, and to test how to save myself in a cold water dunking. I have found that with my pfd, I go under water, then immediately my head rises above the water before I get the cold water gasp. After the cold water gasp, I either drain the water from my canoe, or I hold on to the gunnel and swim myself and the canoe back to shore. I also have found that even with the canoe completely filled with water, it will float with the gunnel just below the surface of the water.