If there’s one thing that basically every fan base complains about, it’s their coach shuffling lines. As long as I’ve been a hockey fan reading hockey commentary on the internet, I’ve been reading complaints about it. The infuriating thing is that very few people watch teams other than the one they support with any regularity, so it’s almost certain that nobody really has a firm grasp on whether or not the coach of their team actually juggles lines with inordinate frequency. They just complain about it.



The Athletic is nothing if not committed to facilitating data driven moaning. A tool is needed to identify coaches who juggle the lines more often or less often than others. Accordingly, I have developed the Line Juggler Index, or LJI for short. The LJI is the percentage of 5-on-5 time with three forwards on the ice that is played by the four most commonly used unique lines in that game. If a coach only has eleven forwards dressed for the game, the...