[oil pan 4]

The only link that was worth anything was the nasa link. The diluted HHO believers saw it as evidence HHO works. I see it as the best evidence that it does not work.
In the link nasa bottle fed an engine on a dyno hydrogen gas. At the most efficient ratio of hydrogen to air it only increased the engines fuel economy 3%.
The ratio of hydrogen to air was several cubic feet per second, vastly many more times the gas then a bank of HHO generators could produce let alone what a car alternator could power.

That right there gives you everything you need to know about HHO generators and why they don't work.
First the hydrogen gas came from a bottle in huge amounts that you could never get from an HHO generator.
The engine didn't have to turn an alternator to make the hydrogen.
The fuel economy increase was only 3%, which can be achieved by adding just about any flammable gas to an engines intake air. Which is nothing special.

I wouldn't say hydrogen doesn't work, it just preforms as expected, as in no miracles.

To put things into perspective, adding a very elaborate and dangerous flammable gas induction system to a vehicles intake can net you up to 3%, but doing an alternator delete has been good for around 5% and in some cases up to a 10% fuel economy improvement.