When talking about defensive rankings, most people, media especially, use a defense's total yards allowed per game average to talk who can and cannot play defense.
Using these rankings, there are six teams ranked in the top-16 who have records under .500. In fact, two of the top four defensive teams, San Diego and Dallas, are sitting in last place of their division. Additionally, two more last place teams, San Francisco and Carolina, are ranked 10th and 12th. For all their defensive prowess, these teams have a combined record of 4-18.
On the flip side of these rankings, 11 of the bottom 16 defenses are at or above .500 for the season. Additionally, eight of those defenses, along with New Orleans and Miami, are also in the bottom 16 in terms of defensive DVOA.
Do you see what I am getting at here? Aside from the fact that yards allowed aren't the be-all, end-all for determining success, the Texan defense is bad, but, in this flukey year, it's not an isolated case of "bad defense, good team." Using these rankings, good defenses are on bad teams, and a number of good teams have average-to-bad-to-very bad defenses.
Yes, the Patriots are lauded as a top-five team with legitimate Super Bowl aspirations while they have the 30th-ranked defense. At the same time, Houston isn't inspiring any confidence with football analysts or fans with their 31st-ranked defense. Heck, people talk about Washington as a NFC playoff contender, but no one is even mentioning their 32nd-ranked defense.
At this point, the questions have to be asked: Why is the New England defense good enough for a contender while the Houston defense keeps the Texans from being in that conversation? What is the difference between the two defenses/teams? Could these be the reasons while the Patriots get a pass for their defense?
- Reputation? It's likely since the Patriots are proven champions with a defensive mastermind as a coach. Talking them up as an elite team has become common practice.
People are afraid of backing the Texans after years of let-downs? Possibly; the trendy pick hasn't come through to make the media look like geniuses.
- The Patriots having a better offense? No, the Texans are gaining more yards while offensive points are roughly similar.
- The Patriots must be dominating with sacks and turnover differential, right? No, the Texans and Patriots each have 10 sacks, and Houston is only behind 3 in turnover differential (-1 to +2).
There may be truth in the first two reasons, but the substantial difference is...well, nine points in per game scoring differential.
Behind some special teams touchdowns, the Patriots average 30.8 points per game to Houston's 25.5. Defensively, the Patriots allow 23.2 ppg to Houston's 27.8. That's what is keeping people off of New England's defense - some timely special teams plays and holding one of an opponent's scoring drives to a field goal as opposed to a touchdown. If you're wondering, Washington's defense allows 19.8 ppg despite being dead last in total offensive yards allowed.
Below there is a comparison of the 4-1 New England defense, for the "elite contending" team, and the 4-2 Houston defense, for the team that people aren't so sure about. Before you look at the comparison, here are the questions I pose to you about this: Are fans and media putting too much focus on the yards and not the points? Given the offense's deadly balanced attack, if the defense could improve ever so slightly and limit teams to a Patriot-like ~23 ppg over the last 10 games...would you feel better about Houston's chances? Is allowing four fewer points per game the difference between a garbage defense and doing just enough for the offense?
||Points Per Game Allowed
||Rush Yards Per Game Allowed
||Pass Yards Per Game Allowed
||DVOA vs. Run (Rank)
||DVOA vs. Pass (Rank)