4MATIC was permanently active and distributed the drive torque between the front and rear axles during normal driving on a high-grip surface. The ratio could be set according to the vehicle configuration, e.g. to 40:60 or 48:52 per cent (front to rear axle).
But he does of course claim that the 4Matic system is overall a better system than the competitors. We also discussed exporting and Mercedes-Benz's experience with cold climates.