I do think it a myth, I used to add water to alcohol fuel in my drag racing days to avoid detonation. I have had fuel I left open for weeks, still ran good just had to use an Enya #3 plug and opened the needle a click or two, no oil seperation.

Even so I wouldn't want to buy fuel with water in it. The fact that I had to open the needle is indicative of the fact that the water didn't burn so fuel consumption will go up. At some point its got to stop burning, if not 20% maybe 50%, certainly before 100%.

[sm=bananahead.gif] Unless you use that pill you put in the tank and fill it up with water.