The guidelines state when paddling with Conn Yak paddlers should wear pfds but on level zero it states its a good idea to wear a pfd. I believe it is club culture and should be club policy to always wear the pfd. Zero O level paddlers will surly move up in ability to more harder rated trips where putting on a pfd after a wet exit and hanging onto your boat at the same time is more difficult . Just my two cents on what I believed was always stressed in the past.