It will depend on how soon the defense will be figured out.
Now I am a Homer for sure, but I say the LOB was potentially the best D ever (hear me out). The LOB was the best Defense in the nfl for multiple years, vs the bears that got figured out very fast.
Tell us you didn't see that Bears defense playing without explicitly saying you didn't see that Bears defense playing.
I'd say it was more Buddy Ryan leaving the Bears that made the Bears defense deteriorate than the league "figuring it out." It was an enormously talented defense that Ryan turned into possibly the greatest ever. Ryan became the Bears' DC in the late '70s and started developing his innovative defensive schemes, but it didn't really all come together until a few years after something really important happened in 1981: Mike Singletary was drafted. Having Singletary turned Ryan's defenses from good or even excellent to great, which they were for a few years in a row, culminating in the most impressive defensive performance I've ever seen. Fewest yards allowed in the league
Fewest first downs allowed in the league?
Most turnovers forced in the league?
Fewest points allowed in the league?
The 2013 Seahawks, my favorite single-season team of all time, also allowed the fewest yards and points and forced the most turnovers in the league. Let's compare them.
First, let's get the easy one out of the way.
First downs allowed: The '85 Bears allowed the fewest first downs in the league, with 236. Washington was close behind at 244. The league-average defense allowed 306.9 first downs.
The Bears allowed about 23% fewer first downs than the league average.
The '13 Seahawks were tied with two other teams for the third-fewest first downs allowed, with 282. The Saints were the best at preventing opponents from getting first downs that year, with 274. The league average was 319.1 first downs allowed. The Seahawks allowed about 12% fewer first downs than the league average. So in terms of comparison to the league average, the '85 Bears were nearly twice as good as the '13 Seahawks. Now let's move on to comparisons that should be closer.
Turnovers forced
The '85 Bears had 54 takeaways (3.4 per game). The next-best team had 48. A league-average team would have forced 38.2 turnovers (2.4 per game, a whole turnover per game fewer than the Bears). The Bears were 12.5% better at taking the ball away than the next-best team, and 41% better than the league average.
The '13 Seahawks had 39 takeaways (2.4 per game). The next-best team had 36. The league-average team would have taken the the ball away 25.4 times (1.6 per game). The Seahawks were 8.3% better at taking the ball away than the next-best team, and a whopping 53% better than the league average. This one is a
much closer comparison than first downs allowed. There are decent arguments both ways.
Yards allowed
The '85 Bears allowed 4135 yards, or about 258.4 yards per game. The next-best team allowed 4320 (270 per game) and the league-average team allowed 5271.1, or about 329.4 yards per game.
The '85 Bears allowed about 4.3% fewer yards than the next-best team in yards allowed, and 18.1% fewer than the league average.
The 2013 Seahawks allowed 4378 yards, or about 273.6 per game. The next-best team allowed 4820, or about 301.3 per game, and the league-average team allowed 5575.7 yards, or about 348.5 per game.
The '13 Seahawks allowed about 9.2% fewer yards than the next-best team, and 21.5% fewer than the league average.
This one goes to the 2013 Seahawks. It really
was a great defense.
Points allowed
The '85 Bears allowed 198 points. the next-best team was the 49ers with 263, and the league average was 344.5 points.
When the Seahawks allowed opponents to score 231 in 2013, the Panthers were close behind at 241, and the league average was 374.5.
The '85 Bears allowed 25% fewer points than the next-best team and about 43% fewer than the league average.
The '13 Seahawks allowed 4% fewer points than the next-best team and about 38% fewer than the league average.
This one goes pretty clearly to the Bears.
The '85 Bears was a team that ran roughshod over the entire NFL for a whole season except for one game against the then-good (Dan Marino, Don Shula) Dolphins in Miami during which Ditka, unable to handle the fact that Buddy Ryan was more responsible for the Bears' success than he himself was (and the fact that the players had wanted Ryan to be promoted to head coach when the previous coach was fired), started a fistfight with Ryan, with the Bears players having to separate the two. Despite all the tension between Ryan and Ditka all season, the Bears managed to crush the rest of their opponents, including national-TV curb stompings of the 10-6 Parcells Giants by a score of 21-0 in the divisional round of the playoffs and the 11-5 John Robinson Rams (who for their part had managed to humiliate the 10-6 Landry Cowboys 20-0 on national TV in the divisional round) by a score of 24-0 in the NFC Championship Game. For those of us who saw the games, the domination was even more complete than those scores suggest. Watching the Bears' defense that year, especially in the playoffs, was like watching somebody playing a football video game on a difficulty level about two or three levels too low for his video-game skill.
The Bears ended up 15-1 in the regular season, scoring 456 points and allowing 198, for an average score of 29-13 over the course of the entire season. Can you understand how crazy-different that is from the Seahawks' impressive performance (part of my favorite NFL season of all time, with the distant second place being the magical 1983 season)? It's truly impressive that the 2013 Seahawks scored 417 points (eighth in the league) and allowed 231 (obviously first in the league), but what the '85 Bears did was just nuts.
The '85 Bears is a team that was second in scoring in the league despite having Jim McMahon as its quarterback. Ditka was named Coach of the Year, which was total nonsense, given that he wasn't even responsible for the team's success, as everyone except the Bill Swerski Superfans (and millions like them in the Chicago area, and I know of what I speak here, because I lived in Chicago in 1987-91) could see. Well, everyone except them and the dumbasses in New Orleans who hired Ditka in the late '90s to ruin their team's chances for years.
I still really dislike Buddy Ryan even though he's been dead for years, and I unfairly transferred some of that dislike to his sons except when I thought the Rex Ryan Jets might be a thorn in the hated Cheatriots' side, but what that man did with the Bears' defense in 1981-85 was simply incredible. After Singletary was drafted, the team allowed the 14th-least points, 13th-least points, fifth-least points, and third-least points in the league (notice the trend?) in the 1981-84 seasons. And
then came the '85 Bears. It's utter nonsense to say that a team that had had a top-five defense for three years in a row only had one good season. Additionally, Ryan actually did pretty well with the '78-'80 defenses, but it was when they put Singletary in the middle that magic started to happen.
The LOB did it when offenses were the most dynamic we have seen, and the athletic abilities of the players were way different than the 80s. The LOB could play in any generation! Imagine if they were able to play in the 80s with the lax rules they had on physicality and player health. Unreal!
The other way to look at this is that if players from the '80s had had access to the nutritional and training advantages and schematic education of those in the 2010 decade, their performance could have been even more impressive.
Comparisons between eras are difficult, but as dominant as the Seahawks defense was, the Bears' was even more so. Comparison to contemporaries in percentage terms is one way to try to get around the difficulty of cross-era comparisons.
As stated above, the '85 Bears allowed 25% fewer points than the next-best team and about 43% fewer than the league average.
The '13 Seahawks allowed 4% fewer points than the next-best team and about 38% fewer than the league average.
The Seahawks' defense in 2013 was dominant and pretty clearly (to me, at least) the second-best I've ever seen. The Bears' defense in 1985 was otherworldly.
DVOA comparisons are interesting. By defensive DVOA including the playoffs, the '85 Bears defense (-36.9% defensive DVOA, where more negative is better) wasn't even the best in history. Ryan's '91 Eagles defense (-38.0% DVOA) was, but with the "asterisk" that the team's regular-season DVOA and combined regular-season and playoff defensive DVOA are the same because that team
didn't make the playoffs 
. Also better than the '85 Bears in combined regular-season and playoff defensive DVOA are the '02 Buccaneers (-37.9% DVOA). The '13 Seahawks, at -25.3%, are a very respectable tenth all-time. It's also interesting that Vince Tobin was able to operate the Bears' 1986 defense at a level close to what Ryan had achieved with the '85 defense, close behind at -31.2% in combined regular-season and playoff defensive DVOA.
Can the new generation beat what the lob was? It's possible. I love the concepts, and I hope it's better than what Pete was able to do.
Interesting and innovative defensive concepts without the right roster is basically the 1978-80 Bears, before Singletary came along and made the 46 defense lethal, and that's reason for optimism for Seahawks fans in 2024, if we make the (yes, very big) assumption that Macdonald's scheme will be even nearly as innovative and effective as Ryan's was. Before the Bears' roster was right (
i.e., pre-Singletary), Ryan still had some top-ten and even top-five defenses, and never coached a below-the-league-median defense for the Bears. The combination of Ryan's scheme and the right player in the middle created something special, something I'm still glad I got to see, even though my favorite team had been the Seahawks for nine years before the '85 Bears happened and I am still a Seahawks fan, without having wavered, to this day.
For instance, Pete ran his d. He ran it after rule changes were enacted, or inforced, to stop him. He ran it after teams started drinking and dunking on him. His d was figured out and his adjustments didn't work out.
Pete didn't change his d to matchup against the O. He just ran his d. Sherman didn't follow receivers.
Sherman not following receivers worked out great in 2012-2016. He was first-team All-Pro three times, second-team All-Pro once, and made the Pro Bowl four times in those five seasons. With ETIII in "center field" taking away huge portions of the field from passers and Sherman totally shutting down one side, Chancellor could stay closer to the line of scrimmage and do his "deathbacker" thing without exposing the team via his decent-but-not-great-for-a-DB coverage skills, the defensive line still had time to punish opposing quarterbacks, and with the extra man in the box, the Seahawks didn't allow teams to rush on them. Just because other people do something (like, say, having the best corner follow the best receiver) doesn't mean it's necessarily the best way to do business.
Please note that I didn't even really get into the Bears' total dominance in the playoffs.
They allowed zero points in the NFC playoffs and ten in the Super Bowl, seven of them coming in "garbage time" well after the game's winner had been decided and Bears fans and players were celebrating. At the time, I was living in the town where I grew up in Maine, and it was glorious to hear the total silence about football around there not just the next day, but for months, and to see the Patriots caps, T-shirts, and jerseys disappear from people's wardrobe choices for a good six or seven months. And right about when the Patriots gear was starting to return, it was really nice to go to Foxborough and see the Seahawks pull out the comeback victory in a back-and-forth battle of a game (and see Curt Warner, Largent, Krieg, Easley, and Jacob Green doing their thing, though I'd seen Krieg, Largent, Easley, and Green in Foxborough in '84 too).
That said, I am a Seahawks fan, so I want to be clear that Groundhog Day of 2014 was the best moment of my sports-fan life. The only things that get even close to that day for me are, roughly in order, getting to tell Zorn to his face in 1984, by which time he was the backup QB, that I had had his autographed picture framed on my wall in Kennebunk, Maine for years; following the '94 World Cup with Brazilian friends and even going to three Brazil games (3-0 and 5-0 romps in the group phase and the well-deserved 1-0 semifinal victory against Sweden) and being near the stadium (but unable to come up with $300 for scalped tickets to go in) for the final and the postgame celebration in the streets of L.A.; and following the 2002 World Cup with friends and coworkers here in Brazil, especially the day of the final. And the Seahawks' dominance of the Broncos in XLVIII, while not as complete as the Bears' dominance over the Patriots in SB XX, was against a much better team and especially a
much better offense, so I think the Seahawks' Super Bowl victory, at least, was more impressive than the Bears'.
I love the 2013 Seahawks team, especially that loaded defense, where the combination of scheme and players came together to make magic. I just don't try to convince myself it was actually better than the most dominant defense I've ever seen outside of video games or kids imagining their favorite teams dominating the league while screwing around with a Nerf football on
my somebody's front lawn (the Seahawks may or may not have gone 16-0 and crushed Super Bowl opponents several times in the imagination of a kid all the way across the continent in the '70s and early '80s).
As you can clearly see in the specifics of the comparisons between the two defenses, making such comparisons isn't ridiculous. The '13 Seahawks were not all that far behind the '85 Bears, but even though I have loved the Seahawks for nearly 48 years now, and even though I dislike both Ryan and Ditka, I just can't put the '13 Seahawks defense ahead of the '85 Bears defense.
