I got the 2:08 average possession from dividing their total TOP by their number of possessions. Our D didn't need to be rested against the Lions. It gave up the second TD after a Cowboys' possession of 8:01, and it gave up the first TD on the game's first possession, after resting six days. Edit: that 2:08 is the Lions' average possession, not ours, as you seem to be thinking. But that reminds me that Adam posted our average possession for the season, and our opponents'. I'd be willing to bet the difference was bigger between the Lions' 2:08 and what our opponents had been averaging against us, than the difference between what we'd been averaging on offense and what we had today.