WWW.SNOWMOBILENEWS.COM has a nice page on the new 440. Like that new statingline launch button, very trick.

Can anyone verify yet exactly how the Polaris Magic Red Button works? Here is my guess--the button activates a solenoid in the primary that keeps the weights locked in place while the engine is wound up (simultaneously controlling timing so the engine doesn't blow up). Release the button and the solenoid releases the weights, the primary snaps shut and grabs the belt and you take off like a rocket.
This would sound like some belt damage to me, but it wouldn't matter in snoX where you'd just change the belt before each heat.