you have much more control over detonation when you lower the CR and provide the spark. And you don't have to make everything out of cast iron adamantium

<-- not a thermo guy, though. not by a LONGshot

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I read the article as saying the spark is well after TDC in this engine.

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as are most combustion engines, especially at higher RPM's.

Ignition timing is before TDC. Lots of variables but typically the higher the engine speed the more advanced the timing.

Ignition timing is advanced before TDC in engines because the flame has to have time to propagate. This is why engines that typically see higher RPMS have more spark plugs...

more sparks mean more flame fronts, and a faster burn...

Even this engine will require advanced spark timing for the pressure to spike at the correct time. Too early and the piston will be compressing during the pressure spike, too late, and you lose pressure because your volume is too large.

Valve motion takes time, A/F mixtures burning takes time, that's why I've always been curious about an extra hitch in the crankshaft rotation... something that could leave the piston at TDC for more than an instant...

If you could find a fuel that very predictably auto-ignites, then the flame propagation isn't an issue anymore... once the pressure and temperature reach the correct point, BOOM. It all goes up. Diesels don't already have this, because it still takes time to inject the fuel into an already hot and high pressure cylinder.