I have posted a few articles here recently about the existence of shot quality, one of which related to last seasons Washington Capitals and one related to how shot quality varies according to game score but there are still shot quality deniers out there. One of the comments I received from a shot quality denier to those posts was as in depth as “You did it wrong” but offered no further explanation. So there it stands.
Derek Zona and Gabe Desjardins over at Behind the Net Hockey (mostly shot quality deniers) have put up a $150 prize for anyone who can show that shot quality exists. One method they suggested one could pursue to prove such a thing was the following:
Are there players or teams with the ability to drive or suppress on-ice shooting percentage? What are their characteristics?
This prompted Rob Vollman (who I presume is a shot quality denier, my apologies if not) to look into just that and to do so he identified a group of players who had the highest save percentage against while they were on the ice. The theory is, if shot quality suppression was a talent then there should exist players who experience a very good save percentage for their team while they are on the ice. The group of players identified varied significantly from George Parros to Kyle Wellwood to Sean O’Donnell to Marco Sturm. In the end Rob came to the conclusion that these players all had high save percentages while they were on the ice because they mostly played against weaker quality of competition.
But none of them are facing their team’s toughest minutes. If they truly had the ability to suppress shooting percentage, why would Kesler and Burrows hop out against Ovechkin instead of Malhotra? Why would Pronger keep an eye on Crosby instead of O’Donnell? Kudos to each of them for playing their roles very well, but the explanation still appears grounded in Quality of Competition.
And there is the fault in logic.
- Claim: Shot quality doesn’t exist.
- Counter-evidence: Some players do experience higher save percentages while they are on the ice.
- Rational: They do so because they play against weaker quality of competition.
- Claim Confirmed: Phew, my claim that shot quality doesn’t exist remains valid.
Now the whole problem with that theory is the rational part because the rational part requires shot quality to be real for it to be true. The only way you can have a better quality of competition (in terms shooting/save percentage) is to have shot quality exist. If shot quality didn’t exist all competitors would have the same level of shooting percentage talent. The claim and rational can’t both be true, so the logic fails.
And that is where identifying shot quality becomes difficult. Players that are generally good at reducing the quality of shots against are lined up against opponents who are generally good at creating quality shots for. The net result is their talents cancel each other out to some extent making it difficult to identify shot quality driving/suppressing talent just by looking at the numbers in isolation of who they are playing with and against.