If we had 100% parity in the NHL – every team identically skilled at all times – what would the standings look like?  Would every team's record match their talent level?  Would they all finish with a .500 record?
Not a chance.  Remember, each matchup is essentially a coin toss.  And if we toss all those coins, we end up with the green distribution shown below.  Even though every team was identical, we'd expect a wide distribution of record, with one team finishing below .400 and one finishing above .600 every season.
Luck_vs_actual_medium


The actual distribution of winning percentage since the lockout is shown in blue.  Clearly team talent accounts for a significant proportion of the observed record, but pure luck is 38% of it.  When you look at how any given team did in a given season, you absolutely cannot assume that you've seen an accurate reflection of their talent.

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