There is a great article by Doug Farrar over at Football Outsiders from a couple of days ago that does a great job breaking down the Pistol formation and how the Kansas City Chiefs run it.
Farrar breaks down the Chiefs' final, game winning drive against the Raiders last week.
The real effectiveness of the Pistol for the Chiefs was how it helped them on the ground at the end of this drive. After a 12-yard pass to Gonzalez on third-and-9 from the Oakland 40, Thigpen either took the ball himself or gave it to Johnson on each of the next six plays. When the Raiders played a base 4-3, Johnson would veer and roam through defenders, around some quality blocking. If Oakland brought an extra man to the line, Thigpen wasn't shy about taking off just as that blitzing linebacker left a vacated area. 16 plays and 9:24 after it started, the Chiefs' long drive came to a successful end with a two-yard touchdown run.
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