[dcb]

problem is lack of comprehensive testing (and lack positive results). It always seems to come down to unscientific anecdotalness, seat of the pants baloney, or invalid assumptions made during testing, or some other form of mpg stone soup (i.e. the driver was simultaneously fixed and the car tuned up).

carlosw2 was pretty adamant that it helped on a diesel, and there's a hundred odd truckers that have shelled out $4000 to $14000 for an hho system, but that's a stupid amount to pay for a couple electrodes, so I'm not real eager to try it on my diesel, but might if I ever figure out mpg feedback on it first.