Any junior high school car enthusiast can. Let's see your CV since you mentioned it.

Either way, the alternator never stops producing a current even with a regulator and the parasitic drain on the engine from the alternator is limited and fixed, it never goes above a certain amount. So splitting water with the otherwise wasted electricity from the alternator is probably a good use of it to create hydrogen (HHO) which is a much more potent fuel than gasoline and can theoretically boost the MPG since the electricity used to was otherwise wasted.

This is impossible by the laws of physics.

Not if it's simply using wasted energy. ;)

Is the earth flat?

You can't waste energy, you can only convert it.

An alternator doesn't waste energy. The load on the engine varies with the electrical demand (Lenz's Law). If you draw more current then you increase the load.
Sure, the alternator is physically spinning all the time that the engine is running, but that doesn't mean that it is always requiring the same amount of force to turn it.

Waste energy means that the energy that the alternator creates is not always being used, it's just dissipated as heat.

Yes, alternators waste a lot of energy, they are very inefficient. (see video below for proof)

I happened to see this video which explains the way that the HHO works to improve the 20% efficiency of the combustion (gasoline/petroleum) engine.

In the video the fans/blades increase the efficiency just like the HHO increases efficiency of the vehicle. Same principals, different way of achieving an increased efficiency.

So... you're also claiming that this setup somehow harnesses the heat energy from the alternator? That's really the only significant "waste" energy.

There's always a certain amount of the rotational energy that gets lost as heat. That happens whether there is load or not, although it does vary. But the regulator setup means that if you reduce the electrical demand on the alternator, you also reduce the energy required to rotate it, reducing fuel consumption. That's why hypermilers will turn off every single thing on their vehicle that they possibly can, including warning lights and the like.
If you increase the electrical load on the alternator (e.g. by adding a device that produces hydrogen) then you increase the amount of force required to rotate the alternator, increasing fuel consumption and increasing your heat losses.

I’m convinced he’s here to drum up either forum traffic or YouTube traffic.

no one outside of politics exists that is this argumentative with such a poor understanding of science

IDK we now have a generation who have never been told they are wrong and have never been told "no."

Maybe he just needs a trophy.