One of my biggest concerns about a college-football playoff is the problem of playoff creep, i.e. that the number of teams would increase over time. A four-team or an eight-team playoff might end up with the best team winning fairly often, but a 16, 24 or 32 team playoff could have a very low correlation between the best teams and the championship teams. However, there is always going to be a debate about who should be the last team in, so there will always be pressure to include more teams. As further evidence of my point, the NCAA basketball tournament is considering increasing the number of teams from 65 to 96. As a fan of William and Mary, I probably should applaud this as it may be the only chance for my team to finally get to the NCAA tournament. Well, maybe they won't need help this year. Regardless, I think this proposal would have a huge negative effect on the importance of the regular season.
The four key effects on the importance of the regular season:
1) The big conference teams will be able to get in with a lower number of wins. Assume that all of the teams that made the NCAA tournament plus all of the NIT at-large teams plus NIT automatic bid team Davidson would have made a 96-team tournament in 2008. Then add in three additional teams, which using the NCAA's methodology, I guess to be Cincinnati, Houston and Nevada. That would mean the seven BCS conferences would get the following number of teams into the playoffs:
ACC: 9 of 12
Big 10: 9 of 11
Big 12: 9 of 12
Big East: 11 of 16
Pac 10: 7 of 10
SEC: 7 of 12
Only five BCS conference teams with a winning record would have missed out. Three of those teams were in the relatively weaker SEC (Ole Miss, Vanderbilt and Alabama), and the other two were barely above .500, Seton Hall (16-15) and NC State (16-14).
2) The potential 1, 2 and 3 seeds will have less to play for. The key gains for being a 1 seed as opposed to a 2 seed are that you avoid playing the likely other best teams in the country until the Final Four (other 1 seeds) and that you get an easier game in the first round. There has never been a 16 seed to beat a 1 seed and only four times has a 15 beaten a 2. Part of the reason is that the 1 and 2 seeds should be the best teams in the country, but another reason is that the 15 and 16 seeds are substantially worse than even the 14 and 13 seeds. There is a tremendous drop-off in quality of teams moving from 13 to 14 to 15 to 16. The last upset by a 15 seed was in 2001, and one reason for that is because the committee has gotten better at seeding the low seeds. The top teams get a real advantage by getting a top seed, playing a much weaker opponent and it gives them a little incentive to play well during the season. However, if the tournament expands to 96 teams, the 1 seeds will play the winner of the 16-17 game, which will now be a much better team. Last year, it would have included teams such as Kansas State, Kentucky and Tulsa. The old 15 and 16 seeds would now be 23 and 24 seeds and likely out of the tournament by the time the top teams play. The difference between being a 1 or 6 seed would drop considerably.
3) The mid majors would actually increase their at large bids. My projections of last year's tournament would have added at-large bids for the WCC, CAA, MAAC, Southern and MVC (2 teams) conferences. Those conferences had no at large bids last year. The mid-majors' regular season might actually influence their likelihood of playing in the tournament.
4) There would be a big difference between being an 8 seed and being a 9 seed, since the 8 seeds would have a bye and the 9 seeds would not. Teams at this borderline would have an incentive to win their last games to avoid an extra game.
If the key factor is making the regular season meaningful, reasons 1 and 2 argue against increasing, while 3 and 4 would argue in favor of increasing. It seems to me that the first two reasons are more important than the last two. Reason 4 only applies to a particular type of middling team. Reason 3 could be lessened if the committee would select a few more mid-majors for a 64-team tournament. In particular, the large conferences, which get the most attention, would have a particularly reduced importance to the regular season.