Yes, I've seen that video, and the bit with the driver piling rocks under the tire seems fake to me.
There's also this video:
Although here you wonder how much you really care about a vehicle's ability to maneuver through deep mud (assuming you're not driving in Vermont in the spring, that is).
I think the realistic test is handling dirt roads that have potholes, ruts and/or washboards, the kind of obstacles that deter, or slow, drivers in sedans and wagons. Increased ground clearance certainly helps to keep from bottoming out, but you'd also like to know you can hit a pothole without damaging the vehicle.