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And They Said It Couldn't Be Done:
Several years ago, my friends and I decided to test a mix-on-the-go theory of ours. We figured that if we joined several stage bottles through a single manifold, as the first stage was drained, the others would compensate and fill in that stage. In other words, all the stages would balance each other out as the gas was drained. It would be like using a single stage. Only it would be eight of them, joined together. Imagine all that GAS!
But here's the beauty of it: if we used different mixes in each stage, and timed it just right, we could actually alter the mix. We could start with a normal bottom mix, but then as the stages re-mixed we could use them as ascent and finally as deco bottles. And we could do this without having a separate bunch of bottles to keep track of!
Well ... people laughed. But last week, we finally put this to the test. By we, I mean my two buddies; I remained as support diver on a separate gas supply. Sure enough, the whole thing worked, more or less. The fact that my buddies got totally bent and spent three hours in a chamber was really due to their inability to lift the joint stages as the gas was being used up. They gave it a valiant effort, but apparently there's something about exerting yourself underwater that both uses up gas tremendously and apparently contributes to getting bent because my buddies were only half an hour behind their dive profile when they ran out of gas and had to bolt to the surface. We've skipped more deco before without ill effects, but this time they got whammed.
Unfortunately, in all the mess of getting them out of the water and to a chamber, we lost track of the linked stages, so our next trial is going to have to wait until they can go back to work so we can buy new ones.
