Quote:
Originally Posted by Jay Random
Reasonable, but completely uninformative.
PDO does not tell you anything that the separate components, shooting percentage and save percentage, don’t tell you. In fact, PDO gives less information, because it is one number instead of two. A team could have an unsustainably high shooting percentage and very poor goaltending, in which case it would have a PDO of 100 but still be due for a fall in the standings.
In the Flames’ case, they have roughly average goaltending (as measured by SV%) and a very high shooting percentage. The shooting percentage may or may not fall down to earth; because part of it may have been produced by their deliberate tactical choice to pass the puck more often instead of taking low-percentage shots. This may result in better percentages on the shots they do take. Even if not, the fact that they deliberately refrain from taking low-percentage shots will increase their average by omission.
Then consider that the team has had a huge amount of turnover in the past two years, and many of the offensive contributors are rookie or sophomore players. This means that we really have no baseline for what kind of shooting percentage we ought to expect. Is it unrealistic to suppose that the Flames have a lot of good shooters on their team? They didn’t have a couple of years ago – but most of those players aren’t on the roster anymore. Without a baseline, there is no possible way of measuring the deviation that might be attributed to luck.
To make my position perfectly clear:
I have nothing against advanced statistics. I like advanced statistics. But PDO is not an advanced statistic. It is an artefact produced by adding two unrelated statistics together, and it is junk.
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Come to think of it, it tells you less than looking at shooting% and save% do. What about the tabs with an unsustainable shooting% but terrible save%? If you have terrible goalies and middling forwards, there'll still be PDO regression even though it may be near 100. Kind of more obfuscatory tab informative.
Flames are a great example. Save% is average, shooting% is too high. Why should they go to 100 unless you think their forwards can't score???