To be honest,the biggest reason for end of Petty domination originally was that the the Chrysler products were no longer up to the level of the Ford and GM cars, which led to a switch of makes, and they won a championship in a Chevy. They were still doing fairly well, then Dale Inman left, followed shortly after by some of their other top talent, causing Petty to go drive for Mike Curb, where they won a couple of races and were decent, but after Richard went back to Petty Enterprises and that team was never what it was. Also by then, the health issues, numerous injuries and running over 1000 Cup races started to take it's toll. With Earnhardt, I think RCR got a little behind, and then Dale got hurt in the big wreck at Talladega, and then there was the musical crew chief changes, the Larry McReynolds experiment, the new teammate he didn't really want or like, all the while trying to get his own race team off the ground. Through that all, Dale's last season (2000) was his best since 1995, and he seemed to be in top form heading into 2001. As for Jeff, I think his back issues took their toll, he had some GREAT seasons totally overshadowed by even better ones by his teammate, and then at the end got caught in the general decline in the Hendrick cars, but STILL won races and was competitive. Jimmie is still younger than those guys were when they faded, is an absolute physical specimen, and has basically been injury free his whole career. Is Jimmie as good as he was at 35? Probably not, but I'll bet if he had a car on par with the 4, the 18 and the 78, he would still be winning races and at be IN the championship conversation. At some point, his skills WILL diminish, but I don't we are at that point yet.