Why I'm somewhat "meh" to Football Outsiders broken tackles stat system

Listen, I enjoy reading Football Outsiders and I very much appreciate all the outstanding stats work they do. Like Bill Simmons, I'm not a stats guy. I personally feel that football is a game where stats, more often than not, lie about the real truth behind a player, a game, a season, etc. But, what FO does with stats is very unique and, quite possibly, vital to the continued success of pro football.

That said, their broken tackles stats tracking blows.

Well, ok, "blows" is probably not the best term. I guess, for me, the importance of measuring broken tackles is a bit of a head-scratcher. But, before I get into that, I'll post something from Aaron Schatz:

Some people might be surprised to see Indianapolis showing up so high on the list of broken tackles, but that's what happens when you have an undersized defense built around speed.

This is actually quite true.One of the main tenants of the Colts Tampa-2 scheme is to get as many people to the football as possible. "Fly to the ball!" as they say. The purpose of this is to have two smaller defenders do what one normally large defender does: Tackle the ball carrier. However, as is normally the case, most large defenders might be good tacklers, but they are also likely slow. A slow linebacker or defensive back in a Tampa-2 is a useless player. For you "old timers" out there, see Chad Cota.

Regarding the Colts, part of the reason their broken tackle numbers are so high is because their defenders are actually getting to the ball carrier and getting a piece of him. The first guy might not bring that ball carrier down, but the second and third guy will. One may even jar the football loose. This is vintage Tampa-2.

Looking at FO's numbers, the Colts had the most plays of any defense (1071) than any other team. Within those 1071, 81 were broken tackles for a rate of 7.6%, which is second worst of all 32 teams. The Detroit Lions, whose head coach is a big Cover-2 guru, was the worst with a 8.4% and 105 broken tackles.

Yet, the numbers for broken tackles do not seem to suggest teams that were "good" at tackling had stellar defenses. The St. Louis Rams are listed as the team with the least number of broken tackles (58). I don't think I need to go into too much detail as to how bad the Rams defense was last year. #2 on the list are the Denver Broncos, whose defense crumbled in the second half of the 2009 campaign. 

Even the #4 team, the Green Bay Packers, fielded an erratic defense last season. Look no further than their two horrid performances against the Vikings, and their awful defensive effort in the playoffs against the Cardinals. I watched all three of those games. If you are telling me the Packers "tackle well," I'm laughing in your face, stats be damned.

So, while I think this is a great stat to track, and while I am impressed with FO's efforts to track them, I'm not sold on it being an indicator of one team having a better defense than another. Obviously, FO is not saying tackles are the only stat that delineates between a "good" defense and a "bad" one. However, when people see that the Colts defense, which was quite good in 2009, is "worse" at tackling than the Rams defense was, it de-values the importance of the stats.

Indeed, when you see Paul Kuharsky post that Melvin Bullitt had the most broken tackles of any defender in the AFC South, it should not be a suggestion that Bullitt is now a "bad safety," or that he is worse at his position than the horrid Reggie Nelson or the over-rated Michael Griffin. Kuharsky explains:

There are different degrees of broken tackles permitted. I think most of us would agree Nelson and Robinson killed their teams at times by allowing monster plays when they were the last or close-to-the-last guy with a chance to drag a player down. Defensive back missed tackles can have a much more severe impact. (Bullitt and Bethea, playing with such fast help, probably had more guys getting in range to help, at least outside of the New England game.) A safety who played terribly like Michael Griffin is missing here, probably because on his worst plays people were running past him and he didn’t even have a chance to miss.

Again, I think it is great that FO is doing this work, but the system needs some refining. If someone were to tell me that Michael Griffin is a better tackler than Melvin Bullitt, and then toss this stat meter in my face as proof, I'd dismiss them as a Titans homer. I've watched both players, and it's pretty clear Bullitt is better at bringing down a ball carrier than Griffin.

Oh, and speaking of the New England Patriots game from last year, ask Kevin Faulk about what he thinks of Bullitt's tackling skills.