Look outside of HF Boards there are plenty of takes out there.... here's one...
"Vegas started and finished the year as it has done every season since its inaugural campaign: heavy favorites to play in the Stanley Cup Finals if not win them outright. The Golden Knights certainly looked the part in Game One against the Canadiens, cruising to a
4-1 victory.
Montreal then changed tactics, going to a more heavy pressure approach against the Vegas offense with emphasis on regaining puck control and swift counterattacks. It worked; the bulk of Golden Knights goals scored were from its defensemen, and it wasn’t enough as the Canadiens took four of the next five games en route to a Finals matchup against the winner of tonight’s Tampa Bay Lightning-New York Islanders Game Seven brawl to end it all."
A number of commentators on NBC as well as NHL Network have broken this down in even greater detail.
My analysis is that Montreal's D withstood the pressure tactics (2-1-2 stack and spread with pinch D on the weak side) that Vegas fwds threw at them. Montreal absorbed hits, made short outlet passes, maintained composure handling the puck and hung onto the puck forcing Vegas fwds to either engage - and get caught - or swing away. This was evident in game 1. Montreal positioned their fwds defensively in their own zone to pick up centered pucks - or as outlets down at the base of the house to either the left or right of goal posts. In many cases, that player was a Habs winger since the Center was supporting the D below the goal line facing pressure. Staals give away that led to Roy's goal was because the Habs fwd hadn't sagged back deep enough to pick up the short outlet pass. Roy read it and the puck ended up on his stick.
The Avs pulled their center's down low but left their wings stationed on the side boards. They were checked by either the pinching defenceman while Vegas's F3 picked up or blocked the centering pass. Bura's give away that led to the turnover goal was a classic 2 -1- 2 F3 high forecheck. The centering pass hit the Vegas forwards stick and went the other way with no one to counter. Jared's insistence on the Avs playing THEIR game - trying to dictate play - led to their demise. (Not too mention his roster decisions). Vegas scoped all of that out and didn't have to adjust much because of the Avalanche's stubbornness.
All that is part of coaching. Search the net. What you are looking for is out there. Most of the folks on HF are fans with varying levels of understanding of the game. Don't count on finding answers on this board.