Shawn Horcoff’s ugly minus-29 rating last season did not go over well with fans of the Edmonton Oilers. The veteran centre, inked to a long-term big-dollars pact, was in the richest year of that deal. The expectation was that he provide both offence and defence, but in a season where his point totals fell off and his plus/minus wandered into the sewer he became an easy target on a miserable team.

This season, things are different. Horcoff was named captain in the summer, and while the team is still struggling on the ice there is hope off of it. Despite injury, Horcoff’s offence has come around and he has a plus-3 rating on a team that has allowed 46 more goals than it has scored.

Some of that – specifically, Horcoff’s plus/minus – is illusory.

Let’s start by looking at shots for and against while Horcoff is on the ice over the past two seasons. Since plus/minus is primarily a measure of even-strength play, we’ll use Gabriel Desjardins’ five-on-five data.

It’s interesting to note that despite the improved plus/minus, the shot differential while Horcoff is on the ice is nearly twice as bad this season as it was last season. Why then has his plus/minus improved? Simple answer: on-ice percentages.

Looking at the table, we see that the Oilers’ shooting percentage when Shawn Horcoff is on the ice has risen, from 6.8% last season to 9.6% this season. Meanwhile, the team’s save percentage with Horcoff on the ice has also improved, going from a miserable 0.891 to a stellar 0.927.

But while those numbers sound significant, it’s hard to put them in real terms. So let’s take Horcoff’s 14 and change minutes of even-strength ice-time and project it over an 82-game season, with the current percentages. And to make the comparison easier, we’ll go back and do the same thing for last season. Now, despite the fact that the Oilers allow more shots this season with Horcoff on the ice, we see this difference in plus/minus:

That’s a tremendous gap – a +28 shift, based entirely on percentage changes.

Vic Ferrari has persuasively argued that defencemen have very little impact on the save percentage when they’re on the ice; it seems likely that forwards have even less of an impact. We know forwards can impact their on-ice shooting percentage – better passes, better shooting, etc. – to a degree, but I expect what we’re seeing here is the impact of Horcoff having Hall and Eberle as wingers rather than Patrick O’Sullivan and Jean-Francois Jacques.

We know, however, that over time on-ice save percentage + on-ice shooting percentage tends to even out to the 100 range (e.g. an 0.910 SV% and 9.0 SH%). If one were to make the argument that Horcoff is a significantly above or below average offensive player we might expect that shooting percentage to be above or below average; personally I’d suggest reality has it somewhere near the league average mark.

What would Horcoff’s plus/minus look like with his on-ice percentages normalized near the league averages? As follows:

This strikes me as closer to Horcoff’s true level of performance. His plus/minus last year overstated how ineffective he was, thanks to the combination of miserable linemates and poor goaltending behind him; this season it’s probably better than it deserves to be thanks to linemates with strong shooting ability and some good luck with the goaltending.

Whether readers agree with that analysis or not, from 2008-10 Shawn Horcoff has been a textbook example of how on-ice shooting and save percentage can redeem or decimate a player’s plus/minus.