I sail in the ocean. Most of the time it is done solo. I sail as far as 35 miles off shore solo, sometimes to return same day. So there is my qualification to make this statement:

I would never sail solo without being tied to the boat unless there are either a lot of sailors nearby, or a shoreline within a short swim. When I am not tied to the boat, I keep a death grip on the main sheet line.

I have fallen off of a Hobie 16, on a broad reach, without being tied to the boat. The death grip on the mainsheet created enough main sheet tension to create enough mainsheet trim to create enough weather helm to cause the cat to round up to weather and capsize herself. Since I was dragging under the water behind my boat as this system caused automatic sheeting, I named it DUMBASS or Dragging Under My Boat Automatic Sheeting System.

It was not as easy as it may sound. I did not simply hang on to the mainsheet with one hand. When I felt the sheet pulling quickly through my hand, I knew that I would not have enough hand strength to keep the end of the line (I use separate sheet and separate outhaul control lines). I wraped the moving line around an arm and braced for what might try to pull my shoulder off. Using both hands and one entire arm, I was able to remain attached to the accelerated boat.

Don't be a DUMBASS, tie yourself to the boat if sailing off shore, solo.

GARY