Actually, looking through and reading through the dozens of threads on tuner and enthusiast forums, it seems that there's a possibility this might work... or at least not destroy the engine.

The theory of the grooves is that as the piston travels downwards, the grooves cause extra turbulence, which ensures a more even mix of the air and fuel.

As the piston travels back upwards, the grooves, which are aligned to where the spark plug is or slightly off-center of the spark plug, form a channel for the squelch... pushing and concentrating the air-fuel mixture at the center of the combustion chamber.

Unfortunately, there's tons of anecdotal evidence, and no clear dynograph evidence (most of the dynos are of engines that are rebuilt and given high-compression internals at the same time that the job is done).

I'm thinking that it's possible the extra turbulence helps prevent detonation at low rpms that high compression engines are prone to, but by itself, grooving the head may do nothing for your regular street motor.

Another builder has his own technique of doing this... grooving the intake valve area to cause turbulence in the air-fuel mixture before it enters the chamber.

While all of these things may help at idle, I don't know how good it'll work at high rpms. The aforementioned Mazda VTCS, which helps provide good combustion at idle, is often removed by Mazda gearheads as it limits top-end power.

And from some of the dyno evidence, Singh's grooves might do the same.