So, in an 8 team playoff where the 1-8 contest is played in 1's home stadium, we might expect an upset one time in eight games played. If that #8 team often is the leading G5 team, one might expect them to have say a 1 in 6 chance of winning the second round at a "neutral" site, and perhaps the same shot in the NC game. That is pretty low odds of course, which suggests one reality that they shouldn't play in the playoff in the first place.
Or you might accept those odds, a one chance in 8 x 6 x 6, which would happen eventually of course.
That is 0.35%, one shat in 300. Do you think a team with one chance in 300 merits that chance?