[jondumbau]

Nitpicky, but compression release for easy (easier..) starting is already a thing. It talks about completely opening the valves so the starter only overcomes friction. Presumably they're talking about having the cylinders that aren't yet fired spinning over freely? Otherwise it's a very efficient way to spin and engine that can't possibly start without "compressing gasses".

[taneq]

I guess it'd lower the starting torque which might let them use a smaller starter motor? You'd spin the engine for a couple of revolutions, then use the stored kinetic energy to kick start the engine.

[TheSpiceIsLife]

Exhaust valves are open during the exhaust stroke anyway. Inlet valves are open during the intake stroke anyway.

The strongest plausible interpretation of what¹ they're saying is to open valves that are partway through the compression stroke, and open / close any other valves as necessary at the best possible time to promote rapid starting.

1. https://news.ycombinator.com/newsguidelines.html

[jondumbau]

that really makes the most sense. at that point i imagine it would be a more finely controlled compression release. i shouldn't read too much into the wording of what is essentially a marketing statement i suppose :)