its basically engages at 2900rpm or 44% throttle which ever comes first.

the supercharger being on 90% of the time is fine since most of the time your accerlating, which doesn't save any gas anyways.

He even saids at the end of the video at 3:57 time frame if you coast for 30seconds it turns off the supercharger. I'm sure MB believed if your coasting for that long, so basically no or little throttle your on a long highway with little traffic, so dont neeed all that power to accerlate and turns off the supercharger to save gas.

My original point was to contend to the other poster that our superchargers are not on all the time and more then likely probably won't save any more or any less gas then a turbo.

Turbos usually save gas because when your cruising at highway speeds your at a really low rpm and out of boost. Same with the supercharger, at least with ours since its basically turned off at highway crusing speeds.