You should know and remember that when NASCAR made their rules most of their racers where very low budget do it yourselfers that had Oxy/Axectlene(SP?) equipment and knew nothing about the difference in Chrome Moly, DOM, black pipe, mild steel tubing and muffler pipe
Do you know that the FAA specs allow Oxy Axectelen welding of Chrome moly airframes
The low buck roundy round racers of old where and are a different bunch altogether
I've seen many professional drag racers walk away unscathed form horrible crashes, I'm sure the chrome moly chassis and roll cages had a lot to do with that