MisterD,
That's flawed logic. Full-size SUVs and Pickups do the best in Government crash tests, most of these vehicles are body on frame construction exactly like most older rear-wheel drive American Cars. So what your saying is anything that's body on frame is unsafe and monocoque is far safer? If that were the case the pure monocoque constructed 1961 Jaguar XKE would be one of the safest cars on the road, we all know that car's a deathtrap in an accident.
BTW, back in 1989 I saw the aftermath of an accident of a two vehicle head-on collision (both cars were going around 25 mph or slightly slower upon impact). One of the vehicles was a 1988 Jeep Wrangler which had body on frame construction and weighed a little over 3,000 lbs. The other was a 1988 Nissan Maxima which weighed around 3,000 lbs and had unibody construction. The result was the Wrangler had virtually no damage, the only visible damage was one of the sides of the front steel bumper (the side by the driverside front tire) was bent in about an inch or two. The Nissan Maxima on the other hand was totaled, its entire front end was crushed like an accordian. They towed away the totaled Maxima while the Jeep Wrangler drove away.