I always pump the brakes when it comes to narratives about coaches and players having consistent poor results in the playoffs. The playoffs are the ultimate small sample size. And just statistically, the runs that guys like Boudreau have of bad results in the playoffs are completely within reason even if they aren't in any way worse in the playoffs. May seem silly to say, but every player and coach who has ever won the Stanley Cup had never won the Stanley Cup before they won the Stanley Cup.
I mean, take Joel Quenneville, for instance. Now considered a playoff coaching genius, but look at his history leading up to that championship. He was the coach of a very successful St. Louis Blues team that reached the playoffs 7 years in a row under him, and he won five series in that time, making it to the conference finals once. In three seasons in Colorado, he never made it past the second round. Then he heads to Chicago and suddenly is a playoff wizard.
Given the playoffs are under such a microscope, we as fans, and the media as well, just absolutely fall in love with narratives about how every result must have a story behind it. Coincidences and runs of statistically-reasonable bad results just aren't accepted, but it's just the truth of reality. If Thornton never goes deep in the playoffs, it can't just be a run of bad results where his team just gets narrowly edged by another team every year. No, it has to be all Thornton's fault. He must be a choker. Until one year he makes it to the SCF and everyone stops talking about it.
Who's to say it can't be the same with Boudreau, for instance?