Perhaps I'm missing something, but I always thought IROC meant racing identically prepared cars of identical models. That was the idea, anyway: the cars were equal, so the result of the race was due to driving, not car prep or how much money went into selecting exactly the right components to build a winner. As stated in a post above, my old club used to run that kind of a race with cars provided by the host of the race (or one of the better preppers in the club), so that everyone raced the same car on the same lane. (A car for Red, Blue, Green, Yellow—whatever colored lanes and whatever number). We altered that slightly by calling one race series a "Driver's Championship" series that ran the same format, but results counted toward a "Driver's Championship Cup" at the end of the season. I think this is what Bill is proposing. If I'm wrong, please tell me.
The idea was, some guys might be very good drivers, but lousy car preparers, or folks that didn't have the wherewithal to purchase 4 cars to select the best components for one. The IROC or "Driver's Championship" format allowed those people to be competitive in at least one class, because their driving was the deciding factor, not money or skill at preparation. It was a very enjoyable format, and people who wouldn't ordinarily reach a podium actually did so on occasion. (Of course, guys who were the best mechanics and consistent drivers usually won anyway, but there was always the odd chance that somebody else could beat them.) The "Driver's Championship" also allowed club members to try out cars for which classes had not yet been established by the club, such as the Cartrix F1s or front-motored Fly cars. It seemed to be a pretty successful format in the old club. If that's what Bill is proposing, I'm all for it. I like the competition even though I'll rarely if ever make a podium.
But I've always said "The worst day slot racing beats the best day of doing almost anything else..."