I would think you have to take each sail/situation and weigh the odds of flipping, water/air temp, boats around you for rescue, and your sailing ability. If you sail solo and the lake or ocean and no ones around, you better do more than tie yourself to the boat. Radios, cell phones, someone who knows you are out, and warm and dry clothees are a must. I think the juries out on a tether for small cats, but solo on the ocean its a must.