The closest thing I can say I actualy did is in 1995 I took a brand new Dodge Ram 3500 Cummins turbo diesel SLT a $30,000.00 truck for a test drive. The salesman showed and told me how beefy and smooth the suspension was and told me to take a certain set of train tracks as fast as I feel comfortable and the truck will trail straight.
Now these tracks were in poor condition. So I hit the tracks at 10 mph nice ride and each time I turn arround I hit the tracks 10 mph faster. After a few times I hit the tracks at 60 mph and I even let my woman test drive the truck, although she was a mild driver. I called it a night as I didnt want to be on the next episode of Cops. Yep, the truck handled as he said it should and it held together too. So I return with the truck intact and I told the sales guy the top speed I felt comfortable taking the tracks. I saw him checking the truck as I left the dealership. I did wind up buying a truck from him a couple months later but it was a Dakota with the original 10 miles fresh off the truck. I mean, I want to know some crazy knuckle head didnt drive it before me.
Keep in mind I probably wouldnt do it today.
Bob Wolf