"It's simple: I'm saying that choosing one criteria over another is subjective."
That's not the argument. You are saying the choice of a system is subjective. I'm talking about how a particular system functions. I'm saying the function of the division system is not subjective. That's the difference.
Regarding the NFL schedules, I meant to say "near identical schedules." The point is, the teams within a given division play almost identical schedules. In other words, all the teams from the AFC West play basically the same schedule. They have 14 out of 16 common opponents.
The premise behind the division format is that each division/group is playing a nearly identical schedule, so a 12-4 record vs. a 10-6 is achieved against the same competition.
In contrast, a 12-4 record in the AFC West is achieved against different competition as a 10-6 record in the NFC North. That's why each division winner gets a playoff spot, as opposed to simply taking the top 6 teams. Since the teams are playing different levels of competition, you don't exactly know if one team is better, simply based on record, especially since they might not play head to head. That's why a representative from each schedule group (i.e. division) is qualified for the playoff.
Why does the level of subjectivity bother you in how it
functions but not in how the format is
established? If you think about it, it's pretty much a distinction without a difference because the standard in either case is subjectively determined, and after that, the standard is simply being applied. The only concern I have is "is everyone on the committee appealing to the same standard"? That needs to be better addressed and clarified, which involves refining the system, not throwing it away completely.
Anyway, simply having automatic qualifiers isn't necessarily a good thing if the chosen criteria is poorly thought out. The old BCS system had definite qualifiers based on a very complex algorithm/computer system rather than interjecting human opinion. Every team was simply given a score and the highest scored teams faced off. There was no debating anything. Are you in favor of returning to that? If not, why not, since it quells your concerns over subjectivity?
I prefer the current method because deciding which teams are selected by pre-determined means are inflexible, and not accommodating of unforeseen scenarios or anomalies. Such a method is unable to put everything in a proper perspective and go beyond the numbers. In other words, it lacks the capacity to make a more comprehensive assessment.
For example: having automatic bids based on winning a conference may lead to a scenario where such a team goes 8-5 which causes a 10-2 team - one with a more difficult schedule and a more impressive collection of wins - to be left out. One lousy factor overrides a slew of others, which I find absurd. A human committee could recognize how unfair that is and veer things in the direction by which the more deserving 10-2 team gets one of the coveted playoff spots instead.
I'm trying to account for how we've spotlighted this in the discussion, because the main topic is "how many teams should be in the playoffs" (I say four is plenty), not "how should they be selected", although I find both questions interesting.
As for your comments about the NFL:
I'm not fully understanding why it's difficult to compare teams across different divisions. This is precisely my problem : you are making assumptions in advance. You can't just assume that the winner in one division is superior to a second or third place finisher in a different division. Maybe yes, maybe no. There are way too many factors at play. It's easily possible for a team to, say, win the NFC East at 7-9, and then another team could go 10-6 in a tougher NFC West division and finish third and get left out. Sure - you can explain why the winner of the NFC West deserves a spot over the third place team - but you aren't explaining why the 10-6 third place NFC West team deserves to get passed by the inferior NFC East champ. Because they played a similar schedule as their fellow division rivals? I'm not following the logic there.
Anyway, don't want to really fixate on the NFL. I think they are an example of how NOT to do it. There are way too many factors to consider so it's dumb to arbitrarily pick just one as the be-all end-all. Stick with the committee. It works for March Madness and it works for the CFP.