We (Atlanta Region) added SM2 as a regional-only class a couple of years ago at the request of the '97- drivers that felt National had dropped the ball equalizing the various models in SM. Real or not, these guys were staying at home rather than contending for tenth at best (not unlike when IT-7 was created). We ran all of them in the same race amid cries of "participation trophies" (mostly from the '99+ crowd), and overall attendance in that group actually increased when most other groups were not.
Now that National has adjusted the different models for the 2012 we have changed the definition of SM2 to be for the "less intense" driver. As all of you know, it takes a lot of resources (time, talent and money) to run at the front of the field in SM, and not everyone out there is willing to justify that effort. Some (many?) folks want to return to the days when you could run a $10K car and have a chance to contend in the class, but that ship has sailed at the National level. Starting in 2012 Atlanta Region's SM2 class is for all generations of Spec Miatas, but the driver cannot have finished in the top half of the National point the previous year and cannot have run a Pro race (other than Pro-IT) in the past five years. And we'll really depend on the competitors to be enforcing the "seriousness" via peer pressure (and the fact that SM2 counts for nothing other than Atlanta Region points).
Maybe we're watering things down, but if guys are staying home because they don't feel they're competitive then who's that helping? As before, we'll continue to monitor participation levels as a measure of whether it works or not.