I have a theory as to why Indy car has slid in popularity and NASCAR took off in the 90's and plagues the IRL today.

Obviously, it is driver recognition, nothing new there. But why did the most talented American drivers eventually bolt to NASCAR? On the surface many would say money.

But I believe the true reason started in the 60's when the rear engine Lotus came to the Indianapolis Motor Speedway, in 62 or 63? By 65, virtually all of the cars were rear engine in Indy Cars.

The handling of rear engine cars was totally different than the front engine roadsters. A greater finesse was required rather than wrestling the cars around an oval with roadsters. Talented USAC drivers of the 60's 70’s and 80's could make the switch from heavy sprint/roadster cars to light weight rear engines cars. But once that generation had retired off, the new generation of Indy Car drivers had for the most part, very little sprint car experience. If they did have sprint car experience, the NASCAR style fit that bill better than the finesse of the Indy Car. Thus, foreign drivers who had experience in formula cars began to dominate the Indy Car scene because they were more adapted to that style.

Bottom line; the Lotus was a fork in the road that nobody saw coming. It would change not only the Indy cars, but who would eventually drive them.

Indy Car is a European style of driving and NASCAR is a grass roots sprint car style. Neither is superior over the other, just different.

Thus, Danica I believe is very talented but her training is of road racing background, and overcoming her training will be her bigggest challenge not the cars themselves. That is why Hornish, Montoya and others with road racing back ground have struggled

To me it would be like being a free style swimmer all your life and now your going to do a breast stroke style and compete against swimmers who have been breast stroking for years. Expecting to be competive against them is going to have to take time. On the other hand it would be equally difficult be if it were the other way.

I believe if you'd put the NASCAR drivers up against the Indy car drivers on a road course, Indy car drivers would kick their butt as a whole.

Conclusion: Because the the style of cars changed so did the driving techniques to drive them.