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They describe it as being a coil based system that's controlling whether the spark fires (though they didn't go into details) - it seems to me like you'd have to make the decision on each cylinder when before you inject fuel, and ideally control the valves so you don't pump air down the exhaust and screw up the oxygen sensor control loop.
I think you could do it fairly easily on a modern common rail diesel engine, but I'm having trouble seeing how they'd make it work on a conventional gas motor.
Of course, a smaller engine in a hybrid powertrain or an electric car continues to be a better answer.
Walter