Thanks for the feedback. I'm glad you guys enjoyed it. The water was BLOODY cold, but it was still really fun. I sometimes think things become more fun than usual when the conditions are slightly more extreme (I was recently on a bushwalk when a short flurry of snow came down. I couldn't help but strip off and howl into the raging, icy wind).
And Toddo, there are some canyons that don't require any abseils, so it is possible to do a nude trip through one without any specialist experience or gear!