So, That Explains It

From ESPN: Richard Sherman and the Seattle Seahawks' defense shut down the Denver Broncos' record-setting offense as if they knew what was coming.
As Sherman tells it, the Seahawks actually did have a good idea about what plays Peyton Manning and the Broncos were going to run in Super Bowl XLVIII.
Sherman told themmqb.com that Seattle's star-studded secondary was able to anticipate Denver's pass routes by figuring out Manning's pre-snap hand signals during the Seahawks' 43-8 blowout of the Broncos on Sunday.
"All we did was play situational football," Sherman told the website in an interview held during one of the Seahawks' postgame victory parties. "We knew what route concepts they liked on different downs, so we jumped all the routes. Then we figured out the hand signals for a few of the route audibles in the first half."
Sherman had drinks in his hand as he spoke, themmqb.com said, but according to the website he seemed much more interested in talking about the game.
The Seahawks forced four turnovers -- three by Manning, the reigning league MVP who set NFL season records for passing yards and passing touchdowns in 2013. Manning was harassed throughout the Super Bowl and often settled for short passes against Seattle's secondary, which also includes Pro Bowl safeties Earl Thomas and Kam Chancellor.  http://espn.go.com/nfl/playoffs/2013/story/_/id/10403077/super-bowl-richard-sherman-claims-seattle-seahawks-anticipated-denver-broncos-plays-based-peyton-manning-hands
So, the Broncos were not only outplayed, they were out smarted as well.  And even the Seahawks stole the signals, it would not have made a difference in the outcome of the game.