This is an age old issue that people have brought up every year at the beginning of the Area Qualifier season when they go and see "C" riders that are very fast and talented. The rules are in place that allow riders over age 12 who haven't "raced" for more than 2 years (This year being January 1, 2010 as the cut off date) or had an RPV value of 11.0 in 2011 for the C class having raced 6 or more events.
SO, with that being said, there are rules in place to have a legitimate "C" Class group of newer riders that have not been racing more than the past 2 years. BUT there are also plenty of loop holes in the rules to allow riders into the program that don't fit the rules and are outside of the AMA's view.
1 - If you live in an area of the country that doesn't have the AMA as your sanctioning body you won't have RPV Values or # of events for that rider in the past few years. Think CRA in northern Ohio without D 12 anymore. You can race CRA for 4 years and then go to AMA racing and look like you've never raced before anywhere. (Yet if you show the AMA a CRA record of a rider prior to 2010 in competition under a protest, the AMA will remove them from C class), but other sanctioning bodies in other parts of the country don't have good records online for you to research and use for protesting purposes. So living outside of AMA santioning helps riders in the C class who decide to go for Loretta Lynns.
2 - If you've been riding for years but never been racing (just practicing with your buddies at open riding dates), you essentially have flown under the radar long enough to be a good rider without racing before................... you can go into the C class. Many people ride and don't race these days. If they get the bug to try for Loretta Lynn's all of a sudden one year, they are perfectly legal to do so.
Remember, the most famous of all Loretta Lynn's C class champions is Jeremy McGrath. He was a legal C class rider when he won his only Loretta Lynn's title yet was really fast. He started out late but had that natural talent that took him to the top of the sport. So just because someone is super fast in the C class, doesn't necessarily mean that they didn't just start riding 2 years ago.