I'm really not even sure how you'd go about normalizing PDO to then try and figure out a sustainable points/60 number. Rosen has a 5v5 on-ice sh% of 13.91%, over 2 points higher than 2nd, with most being around 8-9. Parayko is in the back at 6.73%. On-ice sv%, he's at 93.33%, which is 2nd behind Tucker with 93.55%, and the others range from 88-90ish.
The point is, Rosen's numbers this season are simply unsustainable. He's playing like the team was last season, when Parayko, Faulk, Krug, Scandella, Mikkola, and Leddy all had on-ice shooting %'s above 10% and everyone except Rosen and Mikkola had on-ice save %'s above 91% during 5v5.
What can we take from these numbers, not a whole heck of a lot. Rosen is playing very well, but it's doubtful he's become a unicorn that magically developed into a quality NHL player at this point in his career. I'm still of the opinion that let him play while he's playing like this on the small chance that he does end up excelling in a 3rd pair role, but it's a certainty that he'll come back to earth at some point.