By Dan Heaning, Sports Talk Philly staff writer 
No team this season has been more underestimated than the Ottawa Senators. From advanced stats nerds to hockey traditionalists, nearly everyone believed the Senators' story would end with the team turning back into a pumpkin, no more so than in Tuesday night's Game 6.
But the team just keeps winning, to the point where they are a winner-take-all Game 7 away from the Stanley Cup Final.
Some will say they had an easy route, blissfully ignoring the Sens defeated the Boston Bruins who had the best regular season Corsi of all the playoff teams. Then outscored one of the better scoring teams during the regular season in the New York Rangers.
How did they do it? One would think as one of the worst Corsi teams during the regular season, it would not be through puck possession.
Yet, Guy Boucher has seemingly altered his 1-3-1 style from his days in Tampa Bay to be more aggressive and work smoother in transition. Sometimes it goes to a 1-2-2. Other times it’s more like a 1-4.
The results, one of the worst Corsi teams in the league during the regular season has turned into a decent puck possession team in the postseason. The Senators style has allowed them to stay in games without sacrificing much in the way of offense as they've come back from two-goal deficits at least once in the first and second round.
But now, since the NHL is very much a copycat league, does this success mean the return of the trap as a mainstream game-long strategy?
Let's not confuse things here. The 1-3-1, 1-4, or 1-2-2 didn't go anywhere. Many teams utilize these formations when defending leads. For example, during Game 2 of the Western Conference Final, the Anaheim Ducks utilized the formations to defend their third-period lead.
The problem with Ottawa's style is that, while it's still not as passive as the 2011 Tampa Bay Lightning's variation, it is a largely passive style of play intent on slowing down the pace of the game much like the New Jersey Devils of the 1990s and early 2000s did.
Back before the Devils perfected the Neutral Zone Trap, the league was very much an offensive game. From 1970-71 to 1993-94, the NHL averaged three or more goals a game. During that time of offensive production, the Montreal Canadiens had also utilized the trap without sacrificing offense.
After 1994, the goals per game number dipped marginally to 2.99 goals per goal then went back up to 3.14 in 1995-96.
However, once the Devils proved the Neutral Zone Trap was a sustainable model by winning the Stanley Cup in 1995 and being one game away from going to the Final a year before, other teams took notice. Clubs like the Florida Panthers and the Senators used their own variation of the trap to achieve success in the years following. The Devils went on to win two more Stanley Cup championships, reached the Final in 2000-01 and were perennially one of the best teams in the league.
While not the Neutral Zone Trap itself, other teams like the Detroit Red Wings utilized trap like styles like the Left Wing Lock. The Red Wings struggled to find success in the playoffs with the style until 1997.
The trap, or at least passive, defense-first styles, had infected the game. Clutching and grabbing became the staple defense and the league-wide save percentage went into the 90s for the first time since the stat was recorded. Games became slow, boring slogs. It was so egregious that the NHL had to severely alter its rulebook during the 2005-06 post-lockout season to discourage the style and encourage goal scoring.
It seemed to work initially, but the goal totals have receded recently. Now, NHL goal totals are only marginally better than the late 90s to early 2000s numbers. These numbers are likely more related to better league-wide save percentages. However, the strategy of clogging up the neutral zone didn't completely leave the game.
It's just that Ottawa has given passive hockey a route to become a mainstream strategy again. That is what should be concerning to hockey fans.
Now the less-talented teams of the league could consider this style to keep themselves competitive. Contending teams could emulate it in crucial games. The result would be a less exciting product on the ice for fans to enjoy.
The proof isn't just in the eye test either. Ottawa’s team Corsi was ranked in between the Winnipeg Jets and the Colorado Avalanche, the league’s worst team, during the regular season. They also boasted the seventh-worst shooting percentage in the league. So, it wasn't like they were capitalizing on opportunities. They just kept games to a crawl.
Instead, Ottawa relies on shot suppression. They finished 12th in shots allowed at five-on-five. Goaltending helped a lot too as the Senators were a Top 10 team in Corsi, Fenwick and traditional save percentage. It wasn't all Craig Anderson either as Mike Condon played in 41 games for the Senators.
The success of the Senators' passive 1-3-1 gives weaker Corsi teams a means to stay in games — slow things down, make the opposing team skate through seaweed essentially. Excitement be damned.
The widespread use of such a style would put hockey in peril just like the Devils' success with the Neutral Zone Trap did 20-something years ago.
With goal scoring still an issue for the league, this is the last thing it needs to contend with. Think of how many more points the Legion of Doom would have produced had the trap not be around. Now the likes of Connor McDavid, Auston Matthews and Patrik Laine could face entire careers with a trap resurgence.
So while the idea of the Pittsburgh Penguins being bounced out of the playoffs is tempting to root for, just remember this. Recall how slow and tedious games from the late 90s and early 2000s were. Recall watching talented teams like the Red Wings sacrifice the offensive potential of their stars to run the Left Wing Lock.
Hockey is on the verge of repeating a senseless and potentially deadly mistake.
