If he did fall in the drink, his only chance to keep from being crushed would have been to dive as deep and as fast as possible. Not possible if wearing flotation.

After reading about a few different capsizes where people have had to swim from beneath a boat (or sails or multihull nets), I'm convinced that inflatable PFDs WITHOUT the automatic inflation feature are the way to go. When you weigh the odds, I think the likelihood of landing in the water unconscious is less than the likelihood of needing to be able to swim out of a tangle (or worse).