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You know, I wasn’t even quite sure how to start a piece like this because there’s been so much swirl around this Islander team, it’s been hard to pinpoint what the perception of them truly is. And that’s when it hit me: no one actually knows what to make of this team.
Sure, there’s been some detracting articles, as well as others looking to see the full story, but ultimately there’s just no real consensus as to how the Islanders sit at 26-15-4 after 45 games.
The hiring of Barry Trotz has obviously been a big contributor. His ability to quickly influence a system to a team that had seemingly forgotten how to play any semblance of defensive hockey seems almost miraculous. Mathew Barzal has become a 200-foot player who is contributing near a point-per-game despite a steep learning curve through the first handful of games.
Anders Lee and Brock Nelson are both on pace for 30-goal seasons. Josh Bailey, Casey Cizikas, and Johnny Boychuk have been stable, veteran presences who are producing on the ice in tangible levels. Thomas Greiss and Robin Lehner, a retread tandem by basically all metrics heading into this season, have combined to be legitimate contenders for the Jennings Trophy. And the surprise production out of Valtteri Filppula and Matt Martin have been the cherry on top to it all.
That is a lot of things that have gone right for a franchise in dire need for a lot of things to go right.
So, performance aside, let’s talk about what we can really make out of this Islander squad. A couple of months ago, I introduced rolling-average charts into the chart library I post on Twitter, and that’s going to be the basis of how we deep dive who this team really is. We’re also going to use Sean Tierney’s league-wide visualizations to put the Islanders’ metrics into context. So let us begin.
Methodical And Cerebral: The Islanders Style
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The first thing we need to identify to truly understand the Islanders is to understand the style of which they play. Barry Trotz is a renowned defensive coach, and his philosophy goes deeper than simply cutting down goals against. That was an obvious objective, of course, for this year’s Islanders after the abomination of the 2017-18 edition. But where Trotz has left an indelible mark has been in the shot rate department.
In the view above, which measures shot attempts for per hour versus shot attempts against per hour, the Islanders are straddling the line between “Dull” and “Bad.” But the improvement really lies within the number itself. This year, the Islanders are giving up 49.01 shot attempts against per hour. Last year, they finished the season giving up 61.87 shot attempts against per hour. That is a decrease of over 20%, which is frankly monumental.
So when we look at rates, it’s important to remember the context of year-over-year improvement, as well as current results relative to the league. At the very least, the attention to detail defensively creates a solid foundation of which the Isles can start to build on offensively. We can measure that by looking at attempt share.
Impact on Shot Attempt & Expected Goals Share
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It’s no secret the Islanders struggled mightily during the first portion of the season. After 10 games, they were barely at the 40% mark of most shot share metrics, a number so astronomically low it was hard to defend much of what was going on. The team was banking points on the back of some unsustainably high shooting numbers, keeping them afloat through October. What’s happened since, however, has been a steady climb into a very manageable attempt share range, mostly in the 48-52% area during a 10-game sample.
However, one of the things Barry Trotz preaches is that idea of the “quality shot.” That’s reflected pretty soundly in the numbers, as the Islanders’ level of high danger chances consistently has trended over their overall shot attempt share.
The same improvement trend shows in the expected goals over time, as we can see below via Sean Tierney (by way of Corsica Hockey):
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This isn’t abnormal for a Trotz team. In fact, Dimitri Filipovic, over at ESPN, outlined a few weeks ago how Trotz teams typically overperform their expected goals for percentage. Looking at one of Tierney’s views below, we can see that’s happening again - the Islanders have an expected goals for percentage of 50.22%, but have an actual goals for percentage of 56.91%.
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Relative to the league, this puts the Islanders (barely) in the upper right quadrant, which is a good place to be. In other words, there’s some clear merit to the fact the Islanders are overperforming. Contextually, we know this is A) typical of a Barry Trotz team and B) not necessarily a negative connotation, given that the Isles still have an expected goals percentage over 50%.
Do We Have To Talk About Luck, Again?
Yes. Sorry. There’s been a lot of conversation about the Isles’ PDO - and rightfully so. PDO is 5-on-5 shooting percentage + 5-on-5 save percentage. League average totals 100, and over time, the expectation is that teams will move towards that average. (There’s a statistical reasoning behind it called the central limit theorem, which essentially states that over time samples will regress toward a normal distribution.)
However, PDO is not predictable. It is a descriptive statistic, which means that it is the output of explaining what already happened. Having a high PDO today does not mean a team will have a high PDO tomorrow. This makes sense, because teams go through hot shooting streaks, cold funks, and typically see normal ebbs and flows of goaltending over the course of the season.
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If we look at how the Islanders are faring here in the vacuum of their own team, over time we’ll see what looks like typical fluctuation. At the moment, their Rolling 10-Game PDO after Game 10 and after Game 45 are bookended in the 104 range, but there are clear drops and recoveries over the middle 35 games.
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But if we extend that out to the league, it paints somewhat of a different story. The Islanders, straight up, have one of the highest PDO’s in the league this season. This is simply a matter of conversion rate - they are executing at beyond expected levels on both shooting percentage and save percentage. And in fact, the Islanders are even considered one of the outliers of the league, which we can tell by them being outside the shaded gray area.
In a vacuum, that seems like a good thing. And to be clear, it’s been good for the results of the team to date. But because these are not predictable nor repeatable metrics, it’s impossible to know how they will fare going forward. More importantly, due to the concept of regression to the mean, we can actually expect some of these metrics to fall.
Eventually. When? That’s anyone’s guess.
Ultimately, at this point you might be asking: does the Barry Trotz system lead to a high PDO? And the answer to that is no.
There appears to be something to the Trotz system where his teams outperform their expected goals on a yearly basis. But that is not a cause for a high PDO. What his system does do is set the players up for success - it does not guarantee it.
Where Does That Leave Us?
This is where the philosophical debate of process versus results comes into play. Right now, the Islanders have 56 points in 45 games. They are right in the thick of the playoff race, and have a clear opportunity to play games into - at least - late April. After the tumultuous summer the franchise just went through, that is unquestionably an enormous win. And in a lot of ways, the stigma of “being the team that John Tavares walked away from” may erase itself to become a “this is a franchise of resilience and energy” narrative. That has an intangible positive off-ice perception impact. One that the Islanders’ franchise has struggled with for years.
If we were to look at what this team is objectively, it’s harder to define. The first month of the season was not good, and the criticism they received during that time was fair and legitimate. But since November, they have been a solid NHL club, and have seen periods of both strong hockey (especially during the time that Josh Ho-Sang and Devon Toews were in the lineup together) and weak points.
One thing is for sure - they are not nearly as bad as some of their detractors say they are. This team is more than just a PDO darling. But there is truth to the fact that they are overperforming their underlying metrics. The goaltending they are getting is, as referenced above, at All-Star levels. They have one of the highest shooting percentages in the league, as well. And all of that does tangibly contribute to the success they see at the moment.
The answer, like most things, is in the middle. This is a solidly average team, overall, that finds themselves in a position to make the most of their roster.
At the end of the day, let’s look at some context. When one considers the last 7 months have included a franchise player walking out the door and prognostications of a last place finish, this season - to date -has been an unexpected, unabashed success.
Thank you to Sean Tierney (@ChartingHockey) for his eyes, charts, and help on this piece.
All data above is at 5v5 play and is from Natural Stat Trick and Corsica Hockey (both noted on all views).