Sean Payton Blitzed b/c He Was Pissed
Thanks to a commenter on Grant Cohn's Press Democrat Site. "The Saints radio guy, Jim Henderson, was on a local radio show...At the 1:30 mark of the interview Henderson says the reason the Saints blitzed so much and pounded the 9er QB’s was because Sean Payton expected a call from Harbaugh during the week of the game so they could reach a gentlemens agreement on how the game would be played. After Harbaugh didn’t call, Payton told Gregg Williams to "turn the dogs loose."

