I don't care about PP assists - those could be anything. Half of them could be tips on shots directed at the net. Nashville's PP has been between meh and awful the last 3 years and part of that is because they ran a 3F 2D PP that looked to feed Subban for slapshots. I can't access power play shot numbers right now, as naturalstattrick seems to be down, but I'd bet Subban is either 1 or 2 in PP shots on that team in that time.
Okay, I actually braved NHL.com and Subban is 3rd behind Josi and Forsberg for PP shots over this time. So Josi's the real offender in this regard. But yeah, I'm not that worried given who the Devils hired as analytics people and what they've done to date with their PP under Hynes.