First, I'm not so sure that's true. There's a whole lot of nebulousness involved in the whole process of rankings. Look at how contentious pretty much all ranking systems are, every year. What possible scenarios can you imagine in which all 4 spots are obviously and clearly delineated? It's easy to imagine a scenario where one spot is obvious: when there's one clearly superior team that should be at #1, or one three extremely good teams and another than just scraped by into fourth. But I can't remember the last time I've ever seen a CFB ranking in which the Top 4 were completely obvious from start to finish with no reasonable arguments for ordering them differently. Making a rule based on some hypothetical scenario in which the pairings are obvious and clear seems kind of pointless when such scenarios are virtually nonexistent. After all, the frequency with which the final rankings were contentious was the reason the BCS was implemented in the first place, and then the reason the CFP replaced the BCS.

Second, even in a hypothetical situation with a clear hierarchy, why should that be the only deciding factor? If (just spitballing here) Texas and Texas A&M were the clear #1 and #2 teams, and the Cotton Bowl were hosting one of the playoffs, it would be stupid to forego that matchup, which would be gigantic for both programs, both conferences, all the fans, the Cotton Bowl, and make for great TV and storylines, just for the sake of making sure the #1 team plays the #4 team in the first round.

If Oregon had been the clear and obvious #1 team in 2014, and FSU the clear and obvious #4 team, does that make it any better? It's still two teams with absolutely no history and no common ground from states just about as far apart as they could be (unless Hawaii makes it), playing in a game that has decades of history hosting Pac and B1G champs, while the B1G champ played elsewhere.