Over the years, many have praised the Bruin's ability to "roll 4 lines". It's gotten to the point where the praise is just slightly ridiculous. Let's examine this Chris Kelly quote that came after a 2-1 win against Arizona in 2014:
"That's our strength, our depth and our ability to roll four lines," Chris Kelly said. "I think a perfect example was the last game where we were able to roll four lines the whole time and I don't know if Phoenix did." - per Metro West Daily News
Now, there's depth, there's wanting everyone on the roster to contribute, and there's what the Bruins used to do.