My closest call was getting caught under a windsurfer sail with a broken cover on a twisted harness line and unable to get past the mast for air.

One's instinct is to go the shortest way and the way of habit. Windsurfing one comes up mast side because that is the shortest distance and where you want to be for rig control.

Unable to pull the harness off the hook and getting very short of air the cold thought went through my mind, pulling harder is not working or going to work, if you don't settle down you are going to die.

Amazing how the sudden seriousness of a situation can focus the mind. In the end I eyeballed the direction of twist, rotated and swam out the other side of the sail. By this time the option was a do or die option, it worked or I would not be writing this, but in retrospect I would have had a lot more time to try other options had I not wasted those few first moments in panic and fruitless effort.

It is the only instance in which wearing buoyancy actually may have compounded the risk, as it prevented me from being able to sink, which would have made it much easier to untwist the harness line.