I also have a very short tether permanently clipped to the mast that I hook into . I once had a German single hander tell me his story of being swept overboard, and though he was on a tether, he was thrown over the lifelines and was drug for some time (he was rail under at the time) and was pretty sure he was going to drown. He did finally haul himself back aboard by virtue of a wave flinging him up and over the lines. He went on to say that if he had been in cold waters, wearing foulies, he would never have gotten back on board. I've never forgotten that story.