My favourite duck dives are when you're in 1' of water and you know you're going to hit a reefy bottom and there's a 6' wall of whitewater bearing down.
^^ Yep ended up with skin and chunks off all but a coupla nuckles after a duckdive in the criticaly worst spot of a wave up north once. And pressures underside of board to go with it (3 week old custom). And it was second surf, first day of the trip