Something about the run-up to the NFL season has been bugging me for years, and it's exemplified by this John Clayton article.

It's a truism that the NFL changes radically from year to year, moreso than any other sports league. And strength of schedule is often cited as a major (in extreme cases, the only) factor for why that's so. But there's a built-in lie there--strength of schedule is always factored, in that analysis, by last year's schedule. But if teams are radically better or worse than the previous year, then it's meaningless to determine strength of this year's schedule based on last year's won-loss record.

Drives me nuts.