Where Dubas potentially failed isn't in insulating the forward group, or the defense that's deeper than it's been in decades, possibly ever.
Where Dubas has potentially failed is the goaltending Jack Campbell has been WELL below average since December and Dubas sat on his ass. I'd be OK with Dubas coming back but I'd tell him don't touch the core and he HAS to go get a #1 goalie, a REAL, PROVEN #1 goalie.
That means Varlamov, Fluery, Gibson, Lehner address it properly Campbell is a backup and that's fine but he's not a legitimate #1