There is a dispute about who wrote about it first on ScubaBoard. I believe it was @nwgratefuldiver. When told his trimix card did not qualify him for nitrox, he asked if he could get any trimix mix he wanted. Told that he could, he asked for 32/0 (For those who don't know, that's 0% helium and 32% oxygen.) That request apparently created a major AHA! moment for the shop employee.There’s a story that went around about a dive shop refusing to fill a nitrox cylinder when the diver showed his Trimix card.