Eastern Conference? More like Leastern Conference. amirite?
But really...Goal Differential can be misleading. Teams can flatter that by piling on meaningless EN goals cruising to wins, or just running up the score in games that are already won. Or on the other end, in "making it look closer than it is" by tacking on some garbage time "catchup" goals.
It's like "voting efficiency" where having a lot more goals for than against over the course of the year is generally a good sign...but it's more important to score the goals in the right games. If you can score enough goals/keep enough pucks out of your net in the right games, there's an "efficiency" in getting those wins. You don't get extra points for winning 5-1. And you lose the same amount of points getting blown out 7-0.