The worst possible scenario has happened. Peyton Manning, arguably the best quarterback of all time, has signed with the Denver Broncos. He is an immense upgrade over Tebow, and already people are saying the Broncos are runaway favorites to win the division. However, that starts to come into question as you look into the details more closely. How good are the Broncos really going to be, and will it be good enough to win the division.
Since this is going to be a long and detailed post, let me just summarize it for those who have short attention spans (or have better things to do with your time). The Broncos will most likely struggle to make the playoffs, and will almost certainly have to play a wild card game even if they do make the playoffs. Most surprisingly, even if Manning is at 100%, there is a significant chance that the Broncos won't even have a winning record. If you want to know why, read on. If not, just go ahead and jump to the comments to complain about how dumb I am for even suggesting that the Broncos might have a losing record.
The State of the Broncos
To understand where the Broncos are going, we must first understand what they look like without Manning. The first thing to note is that what Tebow did is not relevant, and we should instead concentrate on the Orton era. As I explained in a fanpost I wrote during Tebowmania, Tebow increased their chances of winning without actually making the team better. He was able to do that by increasing the chance of an upset, but at the cost of making blowouts more likely. Then they got lucky enough in a couple games to push them to 8-8, which was enough to win the division.
However, the Tebow Broncos team looks completely different than the Manning team will. To judge more accurately where the Broncos are, we have to see how they performed with a normal quarterback. With Orton, the Broncos are about a 4-12 team. They were 4-12 in 2010, and were 1-4 before Tebow took over. I think it is safe to say that with a normal offense, the Broncos are a 4-12 team with Orton at quarterback. Now the question becomes how much of an upgrade is Manning.
Most analysts are falling into the trap of starting with an 8-8 Broncos team. The problem with this is that that team is not similar to the team they will field with Manning. The 2011 Broncos were dead last in the NFL in pass attempts with 429 (the next closest was the 49ers at 451). They also lead the league in rushing attempts at 546. However, in 2010, the Manning Colts were the opposite, leading the league in pass attempts while having the fifth fewest rushing attempts. It's clear as day that the 2012 Bronco offense will look completely different than it did in 2011.
I harp on this point, even though it should be obvious, because I've already seen people talk as if the Tebow Broncos are a good indicator of what the 2012 squad will look like. It should be obvious that the offense will look much more like the 2010 and early 2011 team than it will the late 2011 team. The main difference being that the quarterback will be Manning instead of Orton.
If you still don't believe that a statement like "Well, the Broncos were 8-8 last year, so Manning will improve on that" is severely oversimplified, I don't know what to tell you. I won't have much access to the internet in the near future, so if somebody in the comments tries to argue against me by pointing to their 8-8 record and playoff win last year, please do me a favor and ask them to read this section again.
Win Probability Added Explained
To judge how much a certain quarterback is worth, I will be using Advanced NFL Stats' Win Probability Added (WPA) stat. The idea behind WPA is that it gives you a player's effect on the game. If you have a 50% chance of winning the game at a certain point, and you throw a pass and it increases your chances of winning to 55%, you just gained .05 WPA. If you take a sack and it decreases your chances of winning to 45%, you just lost .05 WPA.
The benefits of this stat should be obvious. It can tell you the number of wins a player is worth. If a player has 2 WPA over a season, the team would have lost about 2 more games had he not been on the team. However, this number should not be taken as gospel. It can be inflated based on plays late in tight games, and deflated if a player happens to have a good performance in a blowout.
The most important thing to know about WPA is that 0 is average, negative numbers are below average, and positive numbers are above average.
What Manning Brings To The Table
Before we talk about Manning, we need to see what he's replacing. How good was Orton?
Looking at just his 2010 and 2011 numbers (since we're only considering the 2010 and 2011 Broncos), Orton is pretty close to average. He's at least close enough to average that we can just say his WPA for those two years is 0 and not be too far off. If we do this, we can just take Manning's WPA numbers and say that's what he will contribute to the Broncos. (If we didn't make that assumption, we would have to subtract Orton's numbers off of Mannings. Since my approximation makes the 2012 Broncos look better than they are, I feel safe in making it.) So, what exactly does Manning bring to the Broncos?
Before I start analyzing it, let's just take a moment to appreciate how good he is. His 7.18 WPA in 2004 is simply astounding. His two other 6+ WPA years are almost equally amazing. In those seasons, he took the Colts to the playoffs almost by himself. I looked at other numbers, and Manning was by far the best quarterback since 2000 (that's the earliest season they have).
Now that I got that over with, let's get real. Barring his three monster years (2004, 2006, and 2009), and also barring his early years (2000, 2001, and 2002), Manning has consistently been between 3 and 5 WPA for the season. So, since he's replacing an average QB in Orton, we can safely assume he'll add between 3 and 5 wins to the Broncos' total. However, since we're starting at only 4 wins, we can say that the Broncos will likely win between 7 and 9 games.If he manages one of his 6+ WPA monster seasons, he can put them between 10 and 11 wins.
We now have a good estimate of how the Broncos will do in 2012. The biggest problem remaining is that, according to this study at Advanced NFL Stats, even the perfect prediction system has a margin of error of about plus or minus 2 games. In other words, if you think a team will go 8-8 next year, you can only really be confident in saying they'll win between 6 and 10 games.
That kind of sucks for us, because we already have a range of possible records. Using this margin of error, we'll conclude that the Broncos will be between 5-11 and 11-5 if Manning has an average year, and between 8-8 and 13-3 if he has an excellent year. However, without thinking about it too hard, I would assume that some of that error is measured by the quarterback's WPA, so that 2 game margin has already been partially included. I think we can be safe in assuming a margin of error of about 1 game.
So, what should we expect from the 2012 Broncos? Because I'm a Chiefs fan, I'll assume that Manning will not have a monster year. I would guess those years are partially caused by the talent around him being better than usual. That means our prediction for their record would be between 7-9 and 9-7, and with our margin of error, that goes to between 6-10 and 10-6. Or, if you don't like ranges and prefer hard predictions, you won't be too far off predicting 8-8.
Believe me when I say that this conclusion is as shocking to me as it is to you. Or, at least it was before I looked at the data. It's hard to imagine a team led by one of the greatest quarterbacks ever would be expected to go 8-8, and has a very good chance of not even reaching .500. But that is the only conclusion you can reach if you honestly assess the situation as it really is. The Broncos, outside of Manning, just aren't very good. If his goal was to win another Super Bowl before he retired, he made a very poor choice in which team to go to. Like Orton, Alex Smith was an average quarterback last year with the 13-3 49ers. They would have made a far superior choice to the Broncos had Manning been chasing Super Bowls.
Where does that leave the Chiefs? Like the Broncos, the 2012 Chiefs will look much more like the 2010 team than the 2011 one. And also like the Broncos, the 2012 team should be superior to that 2010 squad. Although we won't improve as much from 2010 as the Broncos likely will, the fact that the Broncos' ceiling is 10-6 (barring a monster year by Manning), I would have to say the Chiefs are still more likely to win the division than the Broncos are, and are favorites depending on where you rank the Chargers.
To be clear, I am not saying this was a bad move by the Broncos, or that this was good for us. Had Manning not signed with the Broncos, they would likely be the worst team in the division. The addition of Manning makes them legit contenders for the division title (even if they're not the favorites). His decision is bad news for us, but not as bad as some would have you believe.