Something funny has happened since Craig MacTavish made the highly criticized trade that sent defenceman Ladislav Smid to the Calgary Flames in exchange for futures. Smid has imploded with the Flames, and that oh-so-weak Oilers defence seemingly hasn’t gotten any worse.

In fact, Smid’s departure appears to have marked bit of a turning point for the Oilers; after going 4-14-2 to start the year Edmonton won the first game post-Smid and has put together a still bad but much improved 11-14-3 record since.

As interesting as that won/lost record is, it’s nothing close to definitive. A lot goes into a win or a loss and often a team’s record with a given player on it is more luck than anything else. All it does is show that the sky hasn’t fallen in Edmonton post-Smid.

But other metrics show a lot more than that.

There’s something interesting that happens to Flames defencemen when they get paired with Smid: They get worse. Calgary gets out-shot by a 3:2 margin when Smid is on the ice, and no matter who he is paired with the partner has been better off with almost anybody else.

The following chart shows the percentage of all attempted shots taken by Calgary with a given defence pair on the ice. The break-even mark is 50 percent, with higher being better and lower being worse:

For pure puck-moving defencemen, like Mark Giordano and Dennis Wideman, the addition of Smid to their pairing hurt. In Giordano’s case – and he’s the guy most worth paying attention to since a) we know he is an exceptional defenceman and b) he’s played the most with Smid – the difference was roughly 3.5 shots out of every hundred. In other words, Calgary went from being out-shot 52-48 with Giordano and X on the ice to being out-shot 56-44 with Giordano and Smid.

For guys who aren’t puck-movers, Smid was kryptonite. We’ll ignore T.J. Brodie, since the sample size is so small, but Chris Butler and Shane O’Brien both go from being bad without Smid to being outshot 2:1 when paired with Smid.

In short: in Calgary, Smid has been worse than useless when paired with anybody other than an exceptional puck-mover, and even in the latter pairing he has dragged down the results of that puck-mover.

There is an idea floating around that Smid – a big, tough, physical defenceman who knew what do in his own zone – was carrying regular partner Jeff Petry and that with Smid gone Petry has been exposed as a bad defenceman.

It isn’t a theory that harmonizes with available fact. Let’s start by looking at Petry’s numbers with various partners this year:

The idea that Petry’s a trainwreck just doesn’t work because almost everybody he partners with gets better in the process. Petry has played with five regular partners this year, and it’s not a fantastic list – he’s played with Andrew Ference against tough opposition or he’s played second-pair minutes with a rookie (Anton Belov, Martin Marincin) or the remains of Nick Schultz or Ladislav Smid, who we’re discovering has major holes in his game.

Unsurprisingly, Petry’s looked bad at times. More surprising is this:

What about Smid’s Oilers numbers?

We’re looking at pretty small sample sizes here, but Smid was a disaster when not paired with Petry and this season he’s been a disaster with anybody other than Petry, Giordano or Wideman.

Ladislav Smid has been one of my favourite players to watch for a long time. In interviews he comes across as funny, upbeat and a consummate professional. On the ice, whatever his faults, I’ve never had any reason to doubt he was giving it his all. Blocking shots, making hits, taking hits, whatever; Smid was a guy who always showed up.

So it brings me no pleasure to say this: It looks like something has gone very wrong with the player. With numbers like he’s posting in Calgary, he’ll be lucky if he can hang on as a third-pair defender, and only then if he’s playing with a competent puck-mover. Maybe this is all temporary, and he’ll rebound (I hope so; I’ve always liked the way he plays) but this is an awful stretch of hockey for a guy who has three seasons left at $3.5 million.

As for Craig MacTavish, he was harshly criticized for the Smid trade. But right now, it looks like he cleared a bunch of money, added some prospects and moved a player who wasn’t furthering the cause. If trends continue as they have since the trade, that will be a monumental victory for Edmonton’s general manager. At the very least, it may be wise to tone down the rhetoric condemning him for making the unpopular move.

Finally: It isn’t easy to say nice things about Jeff Petry to Oilers fans. He’s a favoured whipping boy and he probably always will be. But it’s funny how good his partners always seem to look. First, it was Smid. Then it was Anton Belov – whose play fell off at right around the same time he got bumped to the third pairing. Now it’s Martin Marincin, a second-year professional in North America who miraculously seems to be handling second pairing minutes in his first dozen games in the majors. Maybe, just maybe, it’s time to ask whether Petry has something to do with that.