No offense, but I'm a big guy and I sweat pretty profusely in the sun with even a shirt on. One of the things I enjoy the most about being on the water is a nice warm sunny day with my shirt off enjoying what little sun (and opportunities we have to sun tan in BC). I would be so uncomfortable on a hot a day sweating like I'd just been doused that I wouldn't even want to be on the water anymore. I'll leave wearing life jackets in 85 degree weather for the anemics, geriatrics, kids, and toothpicks who might blow overboard in a stiff breeze.
I go fishing to enjoy myself. Personally, that would ruin being on the water for me. In all frankness, if I want to go bare titles in what little sun we get in this province I'm going to do that. I'll pay the tickets, or sell my boat before I start doing that in hot weather.