Reminds me in a roundabout way of the upcoming six-stroke technology. Essentially its a four-stroke with an extra two strokes tacked onto the end of the cycle. After the exhaust you have an intake phase with a charge of air only. This air cools the bore and expands before being expelled in the upward stroke. As it travels along the exhaust it combines with nasty combustion products like cabon monoxide and so on, reducing their effect. This 'air phase' is also dubbed to be able to reduce the size of cooling systems by 20%, thus making modern engines lighter and less polluting, due to the aforementioned air effects, whilst retaining 95% or their power under initial trials.
Cheers - boingk