They had been working on this special for the last 15 months with PBS' Frontline, but yesterday they pulled out. Why? They say they didn't have enough "editorial control", although that situation hasn't changed over the last 15 months. Could there be another reason?
The New York Times speculates that there is. They don't come right out and say it, but it's part of the subtext of the entire article.
ESPN knows where its bread is buttered. They may not have been overtly told to back off by the NFL, but with two other full-time sports networks out there now, you can bet there were discussions in the management offices about how wise it was to tick off their golden calf.