After ignoring and then reading this thread I'm with Wing. Don't crash.
It would just not occur to me to worry about government crash tests and who fails and who passes and by how much. All crashes are different. In terms of head on or nearly head on crashes I feel my chances would be greatly improved if all the big body on frame pickups and suvs were off the road...or they be limited to 50 km/h. 
It ain't a government crash test. IIHS is the insurance industry, the folks that make the big payouts. They noticed that cars that have great results in head on and 50% crash tests still killed a lot of people in real life. It turned out that if you move to the side a bit, all of the front end crumple zone protection is nullified, because the protection is all between the wheels. If you slam two cars together front wheel to front wheel, the wheels shear off and enter the passenger compartment and the A pillars break. Meanwhile the side airbags don't inflate, the driver's head slides off the front airbag and into the broken A pillar.
The answer is for all cars to be equipped with my new invention: In for a penny, in for a pound! When the sensors detect an unavoidable crash, the cars try to make it a full 100% front end crash, maximizing passenger safety!
I agree with you: Supercabs, Denalis, Excursions etc should all be limited to 50 kph.
