The Indianapolis Colts were one of 2012’s most fascinating teams. Their rebuild from the bottom of the NFL came in way ahead of schedule, as the 2-14 Colts from 2011 improved all the way to 11-5 in 2012, earning an unlikely playoff berth in the process. Andrew Luck. Reggie Wayne. #Chuckstrong. You remember. The Colts were a fun team to watch and an easy team to root for. In terms of their expectations heading into the season, 2012 was a massive, massive success for the guys in Indy.

As far as 2013 goes? We’ll see. Obviously, if you’ve read some of Grantland’s offseason NFL content from the past few months, I’ve pointed out that there are reasons to think that this year’s Colts will decline, most of which involve metrics suggesting that Indianapolis was pretty lucky to go 11-5 last year. Each team that fits into the sort of statistically lucky categories last year’s Colts team squeezed into will have anecdotal arguments suggesting that it’ll be the team to avoid the decline, but Indy’s case might be stronger than most. In the end, hopefully we can get a clear picture of whether the 2013 Colts will likely be able to repeat — or even possibly improve upon — the success they enjoyed a year ago.

The Case Against the Colts

Their point differential didn’t match their win-loss record: The 11-5 Colts were outscored by 30 points, becoming the first 11-5 team in league history to fail to post a positive point differential. Using the Pythagorean expectation, the Colts had a point differential more commonly associated with that of a 7.2-win team.

That gap between their actual win total and the win total we would expect from their Pythagorean expectation — 3.8 wins — is enormous. It’s the second-largest difference since 1989, with the largest difference coming from another version of this team. The 1992 Colts went 9-7 while being outscored by 86 points, producing a Pythagorean expectation of 5.0 wins and a difference of four full wins. The next year, they went 4-12. The 2013 Colts won’t be that bad.

It’s true that teams who greatly outstrip their Pythagorean expectation often decline the following season. There are only six other teams since 1989 that were more than three wins better than their Pythagorean expectation, and they declined by a combined 22 wins the following season, nearly four per team. If we expand the sample out to teams that were two wins better than their Pythagorean expectation, we get 33 teams, of which 21 declined and seven stagnated. In all, those 33 teams declined by an average of 2.4 wins the following year.

They were remarkably good in close games: Closely correlated to that figure is Indy’s impressive run in tight contests. The Colts were a remarkable 9-1 in games decided by one touchdown (seven points) or less, a category in which the vast majority of teams will win about 50 percent of contests over any length of time. Only two teams since 1989 had won nine one-touchdown games in a single season; they each went 9-3 during their big season, and the following year they were a combined 7-7. But that’s just two teams.

It’s hard to classify teams into a group when it comes to measuring close-game performance, but let’s work with those teams since 1989 that played at least seven close games and won at least 70 percent of those games. There are 84 instances of that happening. The following year, those 84 teams went a combined 308-292-2 in one-touchdown games, winning 51.1 percent of the contests. That’s textbook regression to the mean. Indy won’t be as good in close games again in 2013.

The Plexiglass Principle: Teams that suffer enormous declines tend to improve the following season. That’s a fact that stood in the Colts’ corner heading into last season, when they were a team that had fallen from 10-6 in 2010 to 2-14 in 2011. That eight-win drop made them a likely candidate to improve by a few wins in 2012, although no model would have suggested that they would go from 2-14 to 11-5.

And now, that nine-win improvement stands as an argument on the other side of Bill James’s Plexiglass Principle: Teams that improve by a significant margin in one season tend to give up some of those gains the following year. Just four other teams since 1989 have improved by nine wins or more, but the point still holds if I expand the sample set out to the 34 teams over that time frame that improved by six wins or more in a given season. During the following season, just five of those 34 teams improved, and most declined noticeably. The average team in that group won three fewer games than it had the previous year.

They played a paper-soft schedule: Both Football Outsiders and Pro-Football-Reference.com measure strength of schedule using their respective advanced metrics. They agree on one thing with the Colts: They played the league’s easiest schedule last year. Nine of Indy’s 16 games came against teams that earned top-10 picks in the 2013 draft. They actually lost the first two of those nine contests before winning the final seven. They were 4-3 in the other seven games, but they were outscored by 46 points in the seven tilts, including a 35-point shellacking by the Patriots in New England.

While strength of schedule can be extremely tricky to predict, what has been clear is just how inconsistent it is. The correlation coefficient between a team’s strength of schedule from year to year, using the Pro-Football-Reference.com measure of schedule strength, is just 0.14. If you’re forgetting some junior high math, that means there’s virtually no relationship between the two groups, and that tells us that the Colts’ easy schedule from 2012 has no predicative value for how easy their schedule will be in 2013.

That doesn’t mean that Indianapolis’s schedule will necessarily be tough. The AFC South is a relatively friendly division. They replace last year’s out of division opponents, the AFC East and the NFC North, with the AFC West and the NFC West, the latter of which seems to get weaker with every injury report. As a second-place team, they also end up with matchups against the Bengals and Dolphins, which isn’t too painful of a combination. I don’t think Indianapolis will play the easiest schedule in football again, but it’s still likely to be a below-average slate, finishing somewhere in the mid-twenties out of 32.

Put that all together and … : OK. I tried to whittle down the Colts using these factors and come up with a quick concept that compared them to similar teams. In this case, there seemed to be a simple one: Wins by one touchdown or less over sub-.500 teams. The Colts had seven such wins last season, which was tied for the second-highest total since the merger. There was one team with eight such wins (the 2003 Panthers), seven joining the Colts with seven wins, and 17 more with six wins in those situations, for a total of 25 teams with six or more close wins against below-average teams.

Those teams did not fare well the following season. Only four of the 25 maintained their previous record or improved upon it, and one of those teams was the 2012 Broncos, which replaced Tim Tebow with Peyton Manning. In all, the average team in that group declined by 3.2 wins from its previous total. Many of those teams put up gaudy records by narrowly beating weak competition, and then they weren’t able to repeat the feat the following year. That’s what the Colts are up against.

The Case Against the Case Against the Colts

No two teams are exactly the same, of course, and there are a few factors surrounding the team that might make it one of those special cases that resist regression to the mean. (Do I mean like the 49ers? For a variety of reasons, no.) Indianapolis is a team with some extreme situations worth mentioning, and that starts with the guy under center.

Andrew Luck will be better: I think just about everybody in football believes Andrew Luck is going to be a significantly better quarterback this season, and he obviously wasn’t all that bad last year. His numbers did pale in comparison to his Gang of Four compatriots last year, but he had a few excuses to work with, too. Want one? Football Outsiders charters found that Luck had been knocked down 122 times last season, either on a sack or on a hit after he released a pass. In second place was Aaron Rodgers, who was knocked down just 93 times; Rodgers was closer to 21st place than he was to Luck in first. It’s pretty incredible that a guy taking that sort of beating could do what Luck did, and as I’ll get to in a minute, his protection should be much better this season.

Plenty of quarterbacks have taken second-year statistical leaps, with Peyton Manning standing out as an obvious example. His jump took the Colts from 3-13 to 13-3, so if Luck can repeat Manning’s example, the Colts might actually go from 11-5 to 21-(negative 5). On the other hand, Luck could improve statistically and still be on a disappointing team; he could put up plenty of numbers in garbage time if the Colts are losing in the fourth quarter. Definitely, though, the best defense against regression is a truly great quarterback, and Luck could be that great as early as this season.

More upgrades on the roster than the average team: I wasn’t a big fan of Indianapolis’s spending spree this offseason, but that was more about how much the Colts spent than the quality of the players they acquired. That offensive line should be better with Donald Thomas and Gosder Cherilus involved, with the latter standing out as the most important addition the team made this offseason. Ahmad Bradshaw, the best deal GM Ryan Grigson made over the break, will be an upgrade on Vick Ballard and Donald Brown at running back. The likes of LaRon Landry, Greg Toler, Erik Walden, and Ricky Jean-Francois can be useful assets if employed judiciously and if they are able to stay healthy.

It’s also true that many teams similar to the Colts — teams that were young and made a sudden move into the playoffs — would have spent a lot of money in the offseason. Competitive teams with loads of cap space almost always do, with the current Seahawks standing out as another example of such a team. That said, there’s no guarantee that these guys, moving in most cases into a new system, will necessarily succeed with Indianapolis. When you sign guys in the middle of the market, as the Colts did, there’s a smaller margin for error in terms of their adaptability. And in some cases, the guys they had might have been better than these new talents, and the Colts could have misread the upgrade opportunity. In general, the pure talent level on the Indy roster is higher than it was a year ago. They’ll also benefit from …

Being a very young team: This one is true, but maybe not as true as it might seem on the surface. In terms of snap-weighted age, Indianapolis had the league’s fifth-youngest offense and 13th-youngest defense a year ago. Many of those players will be a year older now, obviously, but Indianapolis should still be on the youthful side of the aging curve and should expect many of their young talents to play better in 2014.

In the case of players like Luck, T.Y. Hilton, and Anthony Castonzo, that’s absolutely true. There are other places on the roster where Indy might be dependent upon older talent. Consider that they’re still heavily reliant on Reggie Wayne (now 34 years old) and Robert Mathis (32) on their respective sides of the ball. They’ve also just gone out and signed a bunch of veterans in free agency, and in only one case (Walden replacing Dwight Freeney) did they get younger in the process. Some of the deals are relative washes in terms of age, but Indy likely took starter-level snaps away from Ballard when they signed the much older Bradshaw to a one-year deal. The Colts are certainly not going to be an old team, but they will have older players in more meaningful spots than people realize.

Their turnover differential should improve: Stats respect stats! The Colts had a turnover differential of minus-12 last year, which was the seventh-worst figure in football. That mostly belongs to a defense that failed to create many turnovers. The Indianapolis defense produced takeaways on just 8.7 percent of drives last season, and only five teams were worse. I’m very confident they’ll force more takeaways this year.

It would seem safe to assume that Luck will throw fewer than his 18 interceptions from a year ago, but there’s a sign that Luck might actually have been … lucky a year ago. (I’m the first person to run into that pun, right? Good.) Football Outsiders charters also credited Luck with more dropped interceptions than anybody else in football last season, and the only regular starter who threw interceptable passes on a more frequent basis was Brandon Weeden. So while I would normally point to the second-year interception-rate turnarounds of players like Peyton Manning and Josh Freeman, Luck’s interception rate might remain in the high teens again this year.

A full year with Chuck Pagano: Finally, the Colts will also get a full season with their head coach in 2013, with leukemia having kept Pagano away from the organization for most of his debut season as coach. I don’t need to address the obvious emotional benefits of having your head coach healthy and happy, but Pagano’s presence should really help on the defensive side, where he spent his entire career as a coach and coordinator. With so many new players fixing to suit up on that side of the ball, Pagano’s ability to fit talent into an unfamiliar scheme will be essential to Indy’s success this season.

On the other hand, the Colts also lost Pagano’s replacement, Bruce Arians, this offseason. Arians took over under obviously stressful circumstances and went 9-3 before turning the team back to a returning Pagano, a performance that earned him the head coach’s job in Arizona. Arians did an excellent job with Luck and a very limited group of receivers last season, and his absence will be a blow.

His replacement is former Stanford offensive coordinator Pep Hamilton, who has already started posturing that the Colts need to get back to basics and run a balanced offense with a power rushing attack, which seems odd to quote as an essential part of winning football for a city that just watched Peyton Manning for more than a decade. Coaches are more concerned with “balance” than they should be, because it can often be an offensive trait that’s defined by game situation rather than a team’s actual play calling. Teams don’t run to win; they get a big lead and then run to kill clock. If the Colts can run the ball well and create play-action opportunities for Luck, there’s nothing wrong with a balanced offense. If balancing the offense means “establishing the run” by plowing Bradshaw and Ballard into the line for two yards on first down every drive, that’s setting the offense back.

And the Verdict Is …

If this were a team without any hope of a significant improvement at quarterback, it would be a cinch that the Colts would decline, and likely by about five games. Luck, though, is so gifted that it’s not impossible to imagine him putting the team on his back and taking over games at key moments. The guy had seven game-winning drives in the fourth quarter last year, and only two quarterbacks since 1960 have produced more in a single campaign. And that was Andrew Luck as a rookie!

With that said, there’s a dramatic disconnect between the record of last year’s team and just about every other measure or indicator of its level of play. Football Outsiders had the Colts at 25th in DVOA, meaning they played about as well on a per-snap basis as the Browns (24th) or Cardinals (26th). Even if Luck improves dramatically, the lack of star talent around the roster (especially star talent that isn’t past its prime) and the dramatic amount of change still occurring with the roster suggests that this will be a consolidation season. The Colts aren’t likely to be terrible with Luck around, but 8-8 seems like the most plausible record for Indy this year. The Colts are still poised for future success, just not in 2013.