Hydrogen burns, very well. We know. Adding anything at all to your gasoline will inrease your mileage, even if only by displacing gasoline- the entire "car" thing is so grossly inefficient that any tweak can be shown to get an improvement simply by looking for one. A Godawful pile of inefficiencies like a ZJ can see a 4 mpg jump due to tidal forces. My POS
Albatross (Non SC MT) was falling apart with over 200k and got 4 over EPA. I couldn't even hypermile it the thing sucked so badly, the best I could do was drive it gently.
Can we explore the reasons why no car company has fielded anything more radical than a gas/electric hybrid system? Yes, car owners are stupid and will blow anything up given half a chance. But why haven't the railroads added anything to their diesel/electric systems? Why hasn't the military? They do stupid things because they're a couple percent more effective than conventional as long as they're not too many times more expensive than conventional.
If something actually works, do it for real. If acetone gives you 22% better mileage, why isn't it a part of every fill up?