Re brain pain.
Have you ever seen the footage of the guy who pioneered accident research.
He was fully strapped into an aircraft seat on a jet sled that rocketed forward and stopped dead. He used to black out, but was fine after 5 mins, it showed that fully supported deceleration was highly survivable, and it simpact on sharp things that does the damage. I find that reassuring when playing treack days (4 point harness!) and will do same in landy if I do trials.
PS yes truck driver would be in a bad way, yorkie everywhere.