What Does The 12 Mean On Alabama Helmet Can Anyone Give Me A Legit Reason Why The SEC Championship Game Winner Won't Be The National Champ?

Can anyone give me a legit reason why the SEC Championship game winner won't be the National Champ? - what does the 12 mean on alabama helmet

I mean seriously, the 3 teams in the Big 12, the alleged great offense, but the best defense for UT or Tech played against the unity and the best player D has played against Texas will. I say just a shame that a game is a c. Alabama, Florida rematch would be the championship game at the national level.