You could safely say I was more optimistic than most about the Bears' chances this season back in August. I did pick them to win the Super Bowl.
Thing is, I expected the Bears to win more in spite of than because of a defense that I felt would be no better than decent. Six games and five wins into the season, it seems clear that they're considerably better than decent. This unit has a chance to take a place at or near the list of Lovie Smith's best Chicago defenses, which is remarkable considering how many key pieces remain that were in their primes when the Bears went to the Super Bowl six years ago.
The numbers are impressive. The Bears are now the NFL's top scoring defense, allowing 13.0 points per game. They also lead the league in interceptions (14) and total takeaways (21). When measured in terms of yardage, the Bears still fare well, but to a lesser degree. They're second in rushing defense (71.3 yards per game) but sixth in total yards allowed (299.3) and just 16th in passing defense (228 yards per game).
While it may not be particularly insightful to say that the yardage stats are an imperfect measure of a defense's true effectiveness, it seems like the Bears are being shortchanged by them. It's rare that the Bears haven't been able to get stops or that opponents have moved the ball with any real regularity on them, in any of their games.
What's hurt the Bears from a statistical standpoint is that they've held so many leads, opponents have been forced to throw often. Opposing quarterbacks have chucked the ball 245 times in six games against Chicago, or just over 40 per game. A reasonably high percentage of those throws have come with the Bears ahead comfortably, playing 2-deep zone coverage and basically giving opponents all the short underneath throws they want.
Case in point was Monday's game against Detroit. Late in that one, my Lion-fan buddy (yes, they do exist) stated that the Lions had probably outgained the Bears. Indeed they had, 340 to 296. Of Matthew Stafford's 261 passing yards, all but 43 came in the second half, with the Lions down by double digits. Stafford threw for 157 yards on the final two drives, by which time the Bears had their secondary, and especially safeties Major Wright and Chris Conte, so deep that I could have gotten open on a 5-yard curl.
Now I can't make the case that the Bears are a lot better than their passing yardage numbers are skewed against them without pointing out that they also have caught some breaks to boost their turnover stats. It's not the Bears defense that caused Lions running back Joique Bell inexplicably decided to reach for the end zone at the 3-yard line, leading to a fumble recovered by the Bears. They're probably not going to continue to take the ball away at a rate of 3.5 per game.
But my larger point is that there isn't a measure by which the Bears don't rate among the very best defenses in the league. If you'd still rather take the 49ers or the Texans, I wouldn't argue, but I would point out that the Bears still haven't played a single bad defensive game yet like virtually everyone else has. If that remains true into January, my Super Bowl prediction could prove prophetic, even if it was made for the wrong reasons.