Thursday's Duels showed the rule changes implemented by NASCAR have all but eliminated the 'two-car tandems' of 2011, we're back to the classic restrictor plate pack racing we've seen for the previous decade or more - for better, or for worse. This means anyone can win, yet will also mean any accident is that much more dangerous. That said though, pack racing is a skill in itself. It takes a lot of effort to work through the draft whilst the cars are moving around, bumping, squirming, side by side for 10 rows! This race marks the Sprint Cup debut of Danica Patrick. FOX may mention this once or twice. Will she win? You'd think not, but one year ago the 500 was won by another series rookie, Trevor Bayne, so anything can happen!