So much for that theory.

The idea that there could be a “bad” undefeated team is based on a few assumptions—most of them ridiculous. First, and most obviously, is the “strength of schedule” fallacy. After going 2-14 last year, the Chiefs were given an “easy” schedule. So, as the argument goes, the team “hasn’t played anybody yet.”

Strength of schedule, though, is a deeply flawed statistic. Teams can dramatically change character from year to year, and Adam Schein at NFL.com illustrates the point nicely with his preseason Super Bowl picks—the Texans and Falcons. Last season, Houston finished 12-4 to win the AFC South. Atlanta had the same gaudy record while winning the NFC South, getting within four points of Super Bowl XLVIII. This year, however, both teams currently sit at an ugly 2-7, and are among the year's biggest disappointments. By the same logic, the “strength” of any given team's schedule can change from week to week, too, based on their performance.

Here's the funny part. The Broncos, who host the Chiefs on Sunday night, have also played a chump-filled schedule. Denver has wins against the same Jaguars, Giants, Eagles and Cowboys teams that are supposedly padding KC's record. In fact, the Chiefs blog Arrowhead Addict broke down the stats and found that the Broncos actually play a weaker schedule than KC. It seems, then, that one of the things that makes a team “weak” is that the Chiefs have beaten them—which is the very definition of circular logic.

So why isn't Denver called the “worst” 8-1 team? One reason is because people overvalue offense while undervaluing defense. Offense, after all, is flashier and easier to quantify. If Peyton Manning throws a touchdown, he gets credit. If Manning throws an interception, he usually gets blamed—even if the interception results from a great defensive play. Similarly, when the Chiefs' defense stuffs a team four times inside the red zone to seal a victory, the opposing offense will usually get cited for failure, rather than the defense getting praise.

Sunday night, Manning will face the Chiefs in the marquee match-up of the season. As long as Peyton is under center, of course, Denver will be hard to beat. If KC manages to steal a victory, though, the nation's sports pundits will likely once more call KC lucky.

But good luck, as the philosopher Seneca said, is what happens when preparation meets opportunity. The Chiefs have prepared brilliantly. Coach Andy Reid's 13-1 record after a bye week suggests they'll do so again. They have seized the opportunity, and that’s been reflected in the only stat in the NFL that truly matters—wins and losses. KC has nine of the former, and none of the latter. Until that changes, they are the league's best team.

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