It also increases air consumption by speeding up one's pulse. I'd imagine heroin, which depresses the respiratory function, is much better for divers trying to lose weight as you keep your teeth and extend your bottom time. That ferry captain might have been murderous, but he was spot on with the diet plan.
I wonder if that's the real reason why Rush Limbaugh had all that Oxycontin, the poor guy was just trying to shed a few pounds.
Back on topic (but still outlandish): As I'm going on a cruise next month (yeah, I know, but at least I'll get in some lousy diving in Puerto Vallarta and Cabo), I've been more active in the cruiseline's forum on cruisecritic.com. There's one frequent poster who chimes in every time someone asks a question about Mexican ports. One claim he makes is that his wife, who supposedly understands Spanish, got off a ship in Cozumel and overheard locals plotting about mugging tourists. She got right back on the ship and they've never gotten off in Mexico since (he has colorful and equally unbelievable anecdotes about other ports as well). Knowing the only mugging that routinely happens to cruise ship tourists in Cozumel is by aggressive vendors legally selling them crap, I've called his b/s twice now on the forum. He no longer repeats the Cozumel story, but it sure is interesting to see others' perspectives on what we all know to be a very safe island.