Bill Barnwell at Grantland talks about the All-22 film that will be made widely available for the public for every game this season. An interesting nugget: "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." Qualified professionals, with All-22 tape, couldn't adequately grade free agents based on their tape. I think some of the tape reviews done around here and elsewhere are very useful to fans, especially recaps of the offensive plays being run. But this quote illustrates the inherent difficulty of watching tape and the limits to what it provides.