I liked his concept of turning off the fuel injectors during downhill deceleration and using the engine as an effective air brake -- then saving the pressurized air in a tank to use as 1) supercharger air for greater hp when needed and 2) run the entire engine cycle as an air engine at slower speeds (city/parking lot speeds).
This engine would also be able to go from 4 cylinder to 3 cylinder to 2 cylinder effortlessly by holding the valves open and turning off the fuel injectors. Gas mileage boosts would have to come with such a smart engine, real serious gas mileage boosts.
Such an engine could swing effortlessly between supercharged fast acceleration mode to high efficiency "drop a cylinder or two" flat surface cruise mode, to airpump decel mode when going down a mountain to airmotor only when creeping around inside a parking deck.
AND, once the technology became widespread, motors get smaller and much less mechanically complicated.
Also, "any fuel engines" become possible on an intentionally high compression 20:1 engines since you are direct injecting the fuel in a controlled fashion on each power stroke it could be anything that pours and flows at your ambient storage temperature.
One now has to ask how long term reliable this valve actuator solenoid thingy will be since you will have 8 to 16 of the little buggers to deal with .....
"Honey, the engine light came on again --- yes, it was the little valve symbol again ---- no, I didn't save the receipts from the last time, I gave them to you. No, check inside the glovebox, if I put them anywhere it was there."