Monday 20 January 2014

The Shot Quality Argument: Why You Should Stop Using It

Right off the bat, I'm gonna say that yes, I do like stats. I'm one of those people. I'm the annoying guy who tells you that David Clarkson's bodychecking doesn't help the Leafs win. I'm the one you want to tell to shut up and have some faith in the team, and that the coach & GM are there for a reason (nepotism and exploiting an insular industry that's resistant to change, but that's a completely different article.) I reference zone starts alongside goal counts, and you don't get why I'm so hung up on neutral zone ice time.  I'm the one who slowly shakes his head when you say that it's the quality of shots that matters and not the number. Shot quality is a thing that really gets my goat sometimes, because unlike most fancy stats that are argued against as being too hard to tabulate in a fast game like hockey, shot quality actually is too hard to calculate. When you examine how goals go in the net, there's actually a shit ton of variables.

It should be established that I'm arguing about quality of shots in the same sense I would about any other metric: as a trend of results and not singular instances. A breakaway generally scores more often than an unscreened point shot. Yes you generally get better shots on a power play. Yes, you generally expect a shot from the red line to not go in. However, the word "generally" doesn't cover instances like Toskala watching a puck slide under him from 200 feet away or Lidstrom beating Cloutier from centre ice. Until Bettman decides that goals get double or triple value for style, Crosby top shelfing a breakaway and Mike Smith's pants lead to the same result.

Who's shooting has as much of an influence as how or where. To go back to breakaways, you can believe it's a quality chance until you realize that it's Tomas Plekanec who has missed on almost every breakaway. Now imagine that he actually scores, but wait! Was the goalie Kari Lehtonen or Devan Dubnyk? If a player who can't score breakaways gets one past a sub-.900 goalie, did the player have a really good shot or did the goalie blow an easy stop? Either way, the result is the same.

The potential results of a shot can be summed up as a binary: goal/no goal. Thanks to the law of averages, given enough time, any stupid possibility can happen. Sometimes, they can happen right next to each other, like in the Canada v. Finland semifinal at the World Juniors. If shot quality dictated the goals, Zach Fucale would have gotten scored on when he left the net wide open, but he gloved the puck in amazing fashion... right before he let the very next shot go over his shoulder short side. If Finland didn't keep its cycle going, the second chance never would have happened. The other factor is Canada falling back into the box instead of attacking the puckholder. This is a demonstration of how high percentage doesn't equal 100%, and low percentage doesn't mean 0%.

The counterpoint to this position could be something along the lines of why would you just focus on taking shots willy nilly which could lead to giving up a big chance, and then you get scored on after just one shot. The important thing to consider here, though, is that shots are an end, not the means. Even if I did subscribe to the idea of varying qualities of shots, the quality of those you can get off is directly reliant on the skill of the players and their ability to execute set plays. It also doesn't change the fact that if you maintain pressure in the offensive zone for long enough, one of those golden chances will come around to put in (in the case of the Habs, they get four or five and whiff on every one). Once again, law of averages.