Actually he "shouldnt" have pressed the DSC because then he would de-activate it. And you want DSC to work in this terrain as opposed to perhaps driving on sand. I have experienced this on sand; LF tyre was in the air and RR was spinning in the sand. Could not get vehicle to transfer power to other wheels, even the LF tyre was stationary. Could it have something to do woth the torque feedback, meaning that there was no resistance on free-wheeling tyre??