I find it interesting that 12 to 14 teams = this 3+5+5 model, but once you get to 16, it's pod city.
I think it is because of some things that everyone "knows" but most people haven't really thought through.
I've spent some time in the past working out hypothetical schedules and anytime you have a divisionless CG with more than one conference team missed you have to follow the rule that no two teams that miss each other can also miss a common third team.
That made it sound extremely complicated so an example will make it easier:
- If Ohio State doesn't play Iowa and Purdue then Iowa and Purdue HAVE to play each other.
The obvious reason is that if you have three teams not playing each other then you have the possibility of ending up with three undefeated teams. Ie:
- If Ohio State doesn't play Iowa and Purdue, and
- Iowa doesn't play Ohio State and Purdue, and
- Purdue doesn't play Ohio State and Iowa, then
- It is possible for Ohio State, Iowa, and Purdue to all go undefeated.
This is important, I think, because while it sucks when your team is one of three with one loss that misses out it is a completely different thing for an undefeated team to miss out. Ie, if Ohio State, Iowa, and Purdue all go 8-1 and my Buckeyes miss the CG due to tiebreakers I obviously would be disappointed but I'd understand and just figure "well that sucks but it happens". However, if Ohio State, Iowa, and Purdue all go 9-0 and my Buckeyes miss the CG due to tiebreakers I'd be livid. My team beat everybody in front of them, how can they not even have a chance at the league title?
In theory you can figure this all out in your head but as a practical matter it is a lot easier to basically create "quasi-divisions" where all the teams in each play each other and then miss some fraction of the other.