Gregg Williams is a multi dimensional genius.
He got into Manning's head, made him rush a few throws, made his pre snap checks assume full blitz, and most importanly of all he prepared his players thoroughly with loads of different looks through film study.
And in the end, thanks to that great defensive preparation, Porter reads the route and play perfectly and gets the pick six to win the Super Bowl. If there has ever been a better endorsement of the phrase 'Fail to prepare, prepare to fail' I'd love to see it.