Before Yeo became the head coach, Allen was floundering so badly he was even sent to minors. You could argue that the Jake Allen we saw in the playoffs is a product of Mike Yeo (and Martin Brodeur). His stifling system allowed Allen to become comfortable in the net and find his game again.
In the series Yeo had a stranglehold on Boudreau and kept squeezing until he was red in the face. Wild never really solved his system until maybe the last game, when it was too little, too late. In the first games even if the Wild vastly outshot the Blues, it was too often one-and-done in the offensive zone. Blues defensemen kept the Wild forwards out of the rebounds. Blues clogged the neutral zone so badly that we barely saw any stretch passes through the middle that were Wild's bread and butter in the regular season. Wild couldn't attack with speed or create on the rush. They were disarmed of their offensive game which was their identity this season.
With that said, would I prefer Yeo as our coach? Hell no. Blues won't win a cup with that playstyle. It's just perfect way to play if you want to upset a superior team in the first round. I also fully expect Yeo-led Blues to hit an epic skid next season. That style of play is so taxing physically and especially mentally and allows so little creativity and freedom to forwards that it's not sustainable over 82 games. Boudreau is a great coach and I'm still happy with him, but his playoff woes are not just bad luck.