I updated the safety section of the blog if anyone cares to comment
Included the following:
A note on leashes
Downwind foiling has one big safety advantage over other offshore activities like offshore kayaking. If you fall out of the kayak and cannot get back in, then you are stuck drifting, which is how most people get hypothermia and then die.
A downwind foil board (a big one5) gives you an ability to easily paddle at ~5km/h for a few hours without too much suffering, and with the wind you can reliably cover pretty large distances, so you have a good chance of self rescue.
However, if you lose your board, you suddenly are in a very dangerous position. Swimming at 1 or 2km/h for more than an hour is unlikely for most, and 2km is pretty close to shore for most downwind runs.
Try shooting your board away from you to simulate a fall, and then swim after it. The foil gives it lift and tilts catching the wind and drifting away very fast.
A leash is the simplest and most important safety device6