The biggest puzzle when it comes to the Pittsburgh Penguins is figuring out just what exactly changed for the team after the 2012 loss to the Flyers. I previously took a preliminary stab at identifying where the biggest issues might lie. That project, perhaps unsurprisingly, has moved along at a glacial pace (too much video to watch and not enough hours in the day). The short of it is that from 2009 through 2012 the Penguins were an elite possession team, but those numbers took a nose dive over the following two years. The summer of 2012 brought significant personnel changes, and likely also witnessed some strategic adjustments. Disentangling what mattered most is the very difficult part.

Part of what makes this so difficult to reason through is that the Penguins continued to put up elite possession numbers even while Crosby and Malkin missed a substantial number of hockey games. (I have to credit a twitter user named Andy Smith for some of these ideas and some helpful conversations along the way. He's a fantastic Penguins follow.) If you go back, Malkin suffered a season-ending injury on February 4, 2011. Crosby was, of course, already out with a concussion. From that point through the end of the 2012 season (playoffs included), the Penguins played 124 hockey games.

Malkin and Crosby only played a small part of those 124 games. Malkin played in 81 games, Crosby in only 28. In other words, Malkin was healthy only 65% of the time during this stretch and Crosby was in the lineup only 23% of the time. The two could have combined to play 248 games; instead they only dressed for 109 games, or about 43%.

If there were ever a time to test whether the Penguins and this system needed those two to succeed, now was it. But the team didn't collapse. It actually embarked on a run of improbable domination. Check it out (stats from War on Ice and league-wide ranks during this span are in parentheses).

PIT from 2/5/11 - 4/30/12 Score-Adjusted CF% 55.5% (1st) Score-Adjusted FF% 55.1% (1st) Score-Adjusted SCF% 54.3% (1st) GF% 52.7% (8th)

That, I think, is astounding. Despite Crosby and Malkin missing major chunks of time during this stretch, the Penguins put up the best possession numbers in the league. So why did injuries in 2013 and 2014 affect the team so much more?

I keep coming back to Jordan Staal. I've written previously about the drop-off in performance that his departure caused. Many Penguins fans recognize that he's a very good player, but I (and others) probably never appreciated just how good. And the same, oddly, goes for Matt Cooke and Tyler Kennedy.

We can analyze this trio by looking at puck possession and points. We'll first need to get some baselines for points. I took the last four years that those three were on the Penguins (2008-12) and looked at all forwards who played 2000 or more minutes. Then I broke the group up into four buckets, with the lower threshold for each bucket representing the cut-off for points from a first-liner, second-liner, and so on. The stats are from Hockey Analysis.

Lower Threshold 5v5 Pts/60 (2008-12) First Line 1.92 Second Line 1.69 Third Line 1.39 Fourth Line 0.72

What this tells us is that players over 1.92 5v5 pts/60 are producing at a first-line rate, and players under 0.72 5v5 pts/60 are below replacement level. The chart below looks at Cooke, Kennedy, and Staal specifically.

2008-12 5v5 Pts/60 Jordan Staal 1.91 Matt Cooke 1.66 Tyler Kennedy 1.98

I'd wager that this doesn't coincide with the memory many people have of these three players. To be sure, it seemed that everyone acknowledged these guys were good, but few were talking about their top-line level of production. You can see that Staal and Kennedy were producing at a first-line rate. And Matt Cooke was no slouch either; he scored just a hair under a second-line rate, so in practice he was straddling the line between third-and-second-line production. The upshot, however, is these three were never actually third-line players.

Possession numbers tell a similar story (stats from War on Ice and for 2008-12).

Score Adj. CF% Score Adj. FF% Score Adj. SCF% Jordan Staal 53.5% 53.1% 53.7% Matt Cooke 52.4% 51.9% 52.1% Tyler Kennedy 55.9% 55.4% 55.6%

Those numbers are very good on their own, but they're all the more impressive given the tougher usage these three had. We can look at this another way by checking out line stats. This is a tool over at Progressive Hockey that collects the puck possession information for specific combinations of forwards (split into three-man units). The chart below contains the line stats for the top 15 lines, sorted by 5v5 CF%, with at least 600 minutes of time together across 2008-12.

5v5 CF% 5v5 GF% 5v5 Zone Start % Seguin-Bergeron-Marchand 60.9% 62% 55% Kane-Toews-Brouwer 59.6% 61.8% 77% Neal-Malkin-Kunitz 59.5% 60.3% 69% Knuble-Backstrom-Ovechkin 57.5% 57.6% 58% Lagenbrunner-Zajac-Parise 57.1% 60.4% 56% Wheeler-Little-Ladd 56.9% 45.6% 62% Kennedy-Staal-Cooke 56.6% 57.9% 48% Horton-Krejci-Lucic 56.4% 64.8% 60% Samuelsson-Kesler-Raymond 56.3% 56% 50% Heatley-Spezza-Alfredsson 55.9% 55.4% 55% Jagr-Giroux-Hartnell 55.9% 64.7% 61% Marleau-Thornton-Setoguchi 55.7% 63.6% 57% Prucha-Hanzal-Vrbata 55.3% 58.7% 49% Ryder-Krejci-Wheeler 54.8% 69.1% 55% Hudler-Zetterberg-Filppula 54.8% 60% 54%

There's a lot of information here but I think that two things stand out. First, this whole group (sans the Staal line) is composed of bona fide top six lines. Many of them are their team's top unit, and nearly all were some of the best forward combinations over this four-year span. That makes what Cooke, Kennedy, and Staal did very special. That line controlled 58% of play at even strength, which was the 7th best mark of any line during this time. They also had about 58% of the goals while out there, too.

Second, Staal's line did this while laboring under significantly more difficult usage. Look at the zone start percentage for each of these lines. Only two of these elite lines had a zone start below 50%. Many are between 60% and 70%. Staal's line, however, had the toughest usage and still managed to put up elite puck possession numbers.

The takeaway from this seems obvious, but also rather "controversial" when you say it out loud: from 2008-2012, Cooke-Staal-Kennedy put up first-line even strength results, which means that the Penguins, when healthy, were able to functionally roll out three first lines. That's an enormous edge in the NHL, and I think it goes a long way towards explaining the team's dominance in 2011 and 2012 despite Crosby and Malkin missing significant time.

This isn't terribly surprising when we look at how Staal compares to elite defensive centers after adjusting for usage (the higher the dCorsi/60, the better the possession results).

Kopitar, Toews, and Bergeron are regarded as not only the best defensive centers in the league, but as simply three of the elite centers in the NHL. When adjusting for usage, Jordan Staal fits into this class. This isn't to conclusively say that Staal is as good as the other three. But the point it drives home is that when you take Staal's much more difficult usage into account, he's driving play relatively as well as the best players we see in the game.

***

I started by noting the Penguins' unexpected dominance over a two-year span despite Crosby and Malkin watching from the press box a lot of the time. It's obvious that the team's play was superb during this stretch, but it's worth trying to figure out just how the Penguins managed to put up these numbers. That answer is surely complex, but the line of Cooke-Staal-Kennedy has to be a big part of it. Despite being known as a third line, they put up points and puck possession that compares favorably to the best lines in the NHL around this time.

That line, no doubt, was driven mostly by Jordan Staal. He was underrated by me and others while he was with the Penguins. But throughout his career, he consistently put up elite puck possession numbers for a guy with little help and tough usage. Replacing a guy like that is damn near impossible. But that doesn't mean the Penguins shouldn't try.