"Heh, thanks, but no, thanks".
Something like that maybe. So it goes with the few NASCAR drivers who might be qualified to make Indycar's World Challenge at the very least interesting. Some have gone so far as to make elaborate and uninformed excuses why 'it wouldn't be fair'. That's simply smart business. Allow the ego to be soothed by that bed of cash you roll around in, realizing that, no matter how badly you want to accept and win that challenge, you don't need it. Money has become to the NASCAR driver what that sweet high-school girlfriend was to the boyfriend whom with she pleaded to keep from getting into another scrap after the football game. The Id has again calmed and protected the Self from the fire of the Super-ego.
I have no doubt a few of the NASCAR drivers might be capable of fairly competing. Most of the NASCAR crowd, in my view, would be more fish out of water than in the reverse and very well know it, despite their 'facts' proving otherwise. Even with top-flight equipment the odds of winning the Challenge are marginal, say 10:1, at best. Probably more like 20:1 for the few NASCAR jockeys capable. I'd put Stewart at the top of the list with a second-tier of Kahne, Gordon, and the like in that 20:1 bracket. The rest, just fish in a barrel.
"You're ON! Anytime, anyplace!"
All the sweet smell of... SUCKERRRRR! You've just stepped into the trap.. er, arena and now you're about to get abused only for the gain of others. Just couldn't keep your mouth shut could you? Now, at best, you could walk away with a $5 million prize, but odds are far more likely you'll will be a lap down by the first pit stop. Only then will the "I should've listened to Mr. France and kept my mouth shut", thought occur, realizing you now have two racing sanctions who don't care for you. Anyone remember what happened to Rocky Balboa when Clubber Lang called him out in public? Yep, that's right, severe ass-whuppin' from the hungrier challenger. Rocky should've listened to Mickey and sailed off into the sunset.
"But I can win this thing! I can be the hero!", you'll say. Yes, and an Offenhauser might fly out of your lower digestive tract. Even odds favorite Tony Stewart knows better and he's not the sharpest knife in the drawer so what does that make you?
Dumb AND Stupid.