Sep 16, 2013; Cincinnati, OH, USA; Cincinnati Bengals defensive tackle Geno Atkins (97) arrives prior to the game against the Pittsburgh Steelers at Paul Brown Stadium. Mandatory Credit: Andrew Weber-USA TODAY Sports
A tip of the hat to player safety concerns, a third factor is the systematic resting of players with minor injuries before they become injuries worthy of the IR. Couple that with the Bye Week and a Thursday Night Football game now far more capable because of a division of labor, key players will have considerably more time between games without increasing the number of games in which they must play.
The biggest counterfactual to this proposal remains the schedule itself. As things stand, the NFL exists in faultless ratios. 32 teams breaks down into 2 conferences with 4 divisions of 4 teams each, synchronizing impeccably into a 16 game season that rotates schedules smoothly year after year to create balance and impartiality. How does an 18-game schedule fit into this Euclidian perfection? Answer: very carefully.
The way schedules are currently formed in the NFL include, each inner-division game played twice (6 games), one inner-conference division on a rotational basis (4 games), and one out-of-conference division on a rotational basis (4 games). The final two games come from the inner-conference teams that finished in the same place of their respective divisions, giving each team 16 games. Considering 18 games, questions begin to surface. Do the additional two games come from inner-conference or out-of-conference?
A far more radical line of thought would be the establishment of expansion teams, realigning conferences, and completely changing the structure of the playoffs in order to realign the symmetry of the League. However, this article is not going to chase that rabbit any further than to say that should 18 games go forward in any manner, such a paradigm shifts might become part and parcel of the whole plan.