This means nothing. The PP started to go south before Marner got hurt if I'm not mistaken and didn't the same thing happen around this time last year?
What's weird is how good we're playing with Marner out overall. Does this mean that Marner helps us on the PP but doesn't help us overall? That was a rhetorical question BTW. I saw Boudreau say last night that we're playing perhaps our best hockey of the year as of late and I don't think he's wrong. Now in theory, take the team that's been playing really well lately, add Marner (and Rielly) to the lineup and you should have a strong contender but I wouldn't be surprised to see them both return and our level of play stay the same, or perhaps go down a bit.
This team is up and down like a yoyo and you never know if they're going to lose to a bottom feeder or look great against a top team on any given night. Bottom line, I wouldn't read much into a small sample size. Marner is one of our best players so our chances are of course better with him in the lineup, just like our chances are better with Rielly despite the fact that our record without him is great. And that BTW is the point - our record with or without any specific player really means nothing whether it's our W/L record, the PP, the PK or whatever else.
But ... but ... but ... he's so literate though.