Right on TMG51, crumple zone is the primary factor in high speed head on crashes, which is what that video shows (likely an UN-survivable crash in most any vehicle). Passenger safety however is also highly dependent on the structural integrity of the passenger compartment, which is why so much effort is put into roll cages in race and drag cars. Much better to have your cage bounce off the steel, glass and pavement around you rather than your face or extremities, ouch. You should check out those crash test videos of the early Chinese domestic autos where the entire vehicle becomes the "crumple zone" if you haven't seen them, it's not a pretty sight!