Comebacks thrill us. Comebacks make our hearts race. Comebacks cause us to stand up and cheer. For all that, though, comebacks do not necessarily provide an accurate measure of NFL quarterback quality. Just ask Tim Tebow, who led five comebacks in 2011, only to find himself a backup on one of the league's worst offenses in 2012. After all, to come back at the end of a game, you must first play badly enough to fall behind. On the other side of the coin, you have a guy like Matt Schaub. The Houston Texans quarterback has put together an 11-3 record as a starter the past two seasons, but has no comebacks in that time because he has provided his team with so many early leads.