Though Robert Griffin III's transcendent season bucked the trend this year, playing for a Top Five team is typically a Heisman prerequisite. Griffin played on by far the worst team of any Heisman winner in recent memory.
Prior to his win, the last 11 Heisman winners had all come from teams that finished fifth or better in the final AP poll. The last winner to come from a team outside the Top Five was Ron Dayne when his Wisconsin Badgers finished seventh.
While the Heisman is an individual award, team success will certainly play a role in determining Barkley's chances.
Though preseason polls certainly can't be taken as gospel at this point, most predictions have USC as one of the top contenders for the 2012 BCS title. The Trojans are a virtual lock to begin the season in the Top Five, and with a schedule that sets up well for success, they have an excellent chance to stay there.
Both Notre Dame and Oregon will have to travel to L.A., leaving an Andrew Luck-less Stanford team as the toughest road test for the Trojans.