When the game was created, they had to make some creative decisions as every conference has 12 teams while the major conferences in D1 had very different numbers, the Pac 10 for instance had 10 teams and the Big East had 13. So they moved some teams around and it looks like St. Mary's got lost in the shuffle as they were also basing all success off of what was currently happening at that point in time. This was around 2000-2005, so teams like Illinois were absolutely elite back then and that is why they have an A+ baseline prestige.