Man, that's the truth! I understand guys in speedos if they're
  doing competitive swimming - that improves the mechanics of
  swimming. Swim meets, etc. But at a beach? Can't think of a
  single reason! The tan? Go in your backyard. To show off? Just
  go to a nude beach and get it over with. Maybe that's where
  speedos could work publically: At a nude beach, a speedo would
  be considered modest.... "