I have argued this point already, so I won't belabor it, but GB is not that good a team. Not challenging that play is the type of mistake bad teams make. It's the type of mistake former Saints offensive coordinator / mediocre head coach Mike McCarthy makes. Those are the breaks you get when you play a bad team. The Falcons avoid those mistakes, and you remember when their opponent makes them because they capitalize. If the Falcons had kicked a FG that drive and lost the game anyway, you would not even be talking about it. Instead, they capitalized, and here we are.