Well if you want the best argument for Dallas, how about this. The Steelers had incredibly strong teams with HFA in 2001 and 2004, and failed to even reach the super bowl. The 2005 11-5 team was not as good but rattled off 3 road wins and then became Super Bowl champs. The Colts went 14-2 in 2005 and were the favorites but lost their first game. It was the 2006 12-4 club that won it all. The best Patriots team was the 2007 club that went 16-0, yet they lost the super bowl while the 01, 03, and 04 editions won rings.
So Dallas had HFA last year and blew it. Maybe like the Steelers, Colts, and Patriots, their best team fails to win a ring, and its their more-flawed editions that go all the way.