so the idea is that once running it may produce enough HHO to take over the inert gas side of the plasma (i.e. run its self and not need a tank of gas) and produce a significant excess of HHO. Which isn't far fetched when considering the temp of plasma compare to the temp needed to consistantly break down the water vapor/steam.
that with a 1500watt usage...you look at the numbers and it really looks good.
oh forgot: before the plasma cutter their was the Atomic Hydrogen Torch/welder. basically an electric arc with hydrogen blown across it. They also used hydrogen and oxygen which worked awsome as well. I think they still use this for under water welding....(not much info out there on atomic hydrogen)