In the Sergei Bobrovsky Player Review, as well as other threads since the Blue Jackets were eliminated from the playoffs, there has been much discussion of why exactly the Vezina front-runner turned into the worst goalie of the 2017 Stanley Cup Playoffs.
The most common theory is that Bob get overused in the regular season. As important as his performance was in the Jackets’ regular season success, it may have left him fatigued and/or worn down and less able to withstand the offensive pressure of a team as talented as the Pittsburgh Penguins.
If this theory were true, you would expect to see some correlation between overuse and playoff performance among other goalies.