I was reading Bill Barnwell's recent article on Grantland (http://www.grantland.com/story/_/id/8070933/the-film-launch-thousand-questions-sources-offseason-stories) about the All-22 film being available for next season, and this stood out to me, especially in regards to the Cards choosing to bring back Levi. He was talking about people making incorrect analysis of the film because they don't know a player's responsibility:
"As an example, consider a center on a typical running play. His job, per the playbook, might be to chip the defensive tackle and assist the right guard in temporarily occupying him before getting to the second level and blocking the middle linebacker, creating a lane for his running back to go through. If all goes well, it's easy to see that the center did a fantastic job. In real life, though, the defensive tackle might do a great job of occupying the two linemen, the center might never get to the second level to perform his second assignment, and the middle linebacker might shoot the gap to make a play behind the line of scrimmage for a loss. If you don't know the playcall, how can you know whether the center's job was to get to the second level and block the middle linebacker or whether it was simply to double-team the defensive tackle? I know of one NFL team that wanted to grade every offensive lineman in football before free agency by having its personnel break down every play and grade the offensive linemen on their performance. What they found, though, was that even trained football eyes are unable to reliably break down what each lineman was supposed to do on every single play without guessing far too frequently, as they would have to do on the play above. They abandoned the project."
This puts the signing into perspective for me. Re-signing Levi was somewhat controversial among fans despite his improved play during the end of the 2011 season. A lot of people thought that the Bills OT Demetrius Bell might be a better option, myself included. It would make a lot of sense, however, that the personnel staff felt much more comfortable evaluating the tape on Levi vs Demetrius because they knew what his responsibilities were on every play. This makes me a little more optimistic heading into this season.
On a side note, I'm pretty stoked for the All-22 film becoming available.