No need for insults. If people don't understand, that reflects on your clarity of explanation. It's a continuous change from:
high vacuum, low HHO generation energy, high flywheel energy loss
low vacuum, high HHO generation energy, low flywheel energy loss
You can choose to operate near one end of that range but whereever it is, you're getting more of something and less of something else.
Either way I think this discussion is all a bit pointless without using numbers or laws of physics. Sure you might get some overall improvement in some area over some other engine. But it's a long way from 30% to 101%. Without 101% this engine design is no use at all. Don't think people haven't been trying every possible configuration of pistons and combustion chambers for the past century or two, as well has electrolysis which is as old as the hills. What you see in use only represents the tiny minority of inventions that ended up being the best at their particular job.
Yea of course people will use waste heat for heating nearby things when they can, that doesn't take an invention, it's just obvious. Like the cabin heater in a car. There's even a domestic appliance which burns gas to generate electricity and uses the waste heat to provide hot water and room heating. You sell the electricity back to the grid and end up spending a bit less on power. I heard those big old computers were connected to their building's heating system to reuse the waste heat. Once I even tried to design a device to store heat from my car's engine while driving, and transfer it into my house when I got home. Turned out to be just too inconvenient. But might have saved a little bit of money.