Buddy's D, Kolb and Aikman

Sports Illustrated's Tim Layden is out with a new book: Blood, Sweat and Chalk; The Ultimate Football Playbook; How the Great Coaches Built Today's Game.

One of the coaches Layden catches up with is Buddy Ryan.

SI.com has posted an excerpt about Ryan and the 46 defense on its Web site.

The 46 was a 4-3 defense, the base alignment Ryan liked best. But it was much more than a 4-3. The 46 was the first defense in modern football in which three interior linemen covered the center and two offensive guards, forcing the offensive linemen to block one-on-one and thus limiting their ability to move or help elsewhere. (Customarily, in a 4-3 defense, the center is uncovered and free to assist in double-team blocks or picking up blitzers. In a 3-4 defense, the defensive ends are usually lined up over the offensive tackles, leaving the guards uncovered.)

Layden also takes a look at Ryan's legacy.

History will hold that Ryan was a genius -- in that generous way the noun is applied to coaches -- both as a motivator and strategist. It will less likely declare him a thoughtful, engaged, defensive scientist who loved nothing more than to doodle formations on a chalkboard, an inveterate tinkerer. But that indeed was Buddy Ryan. Some of those chalkboard creations were modest, variants on the standard; others were outlandish.

AIKMAN AND KOLB

Kevin Kolb has talked about reaching out to quarterbacks like Drew Brees for advice as he prepares for his first season as a starting quarterback.

One former QB who he's been in touch with is Troy Aikman.

"I was just watching some film of him a few days ago," Kolb told ESPN.com's Matt Mosley. "His timing and accuracy was amazing. I just sat there in awe of how the ball always arrived on time. I know he's in the Hall of Fame, but quite honestly, I don't think he gets enough credit for how good he was."

THE EAGLES' O-LINE

Our Q&A with Bill Barnwell of Football Outsiders continues.

How did you evaluate Eagles tackles Winston Justice and Jason Peters - both in the pass game and the run game? Who were the Eagles' best and worst offensive linemen?

A: Well, you can't analyze offensive linemen on a one-by-one basis. OL play is so intertwined with the players surrounding the lineman in question that judging the individual performance of a player on any given play is impossibly naive. We track some stats for offensive linemen, but they're events - things like blown blocks that directly lead to sacks, as opposed to ratings or overall performance metrics.

With that in mind, I don't think you can really say a lot about Peters' season. He struggled to stay fit, allowed six sacks - among the league leaders at left tackle - and led the team with 11 penalties for 178 yards. Ouch. Justice had three blown blocks that led to sacks, a much more palatable total.

Philly was actually best running at left tackle, where they were the third-best in the league by our Adjusted Line Yards metric. Some of the credit for that goes to Peters, but there's a lot of players that have something to do with that - blocking tight ends, pulling guards, centers, etc.

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