I think that if JT is in 90+ land, then he may be one of the only guys scoring. Sure, at least one linemate will be doing nicely if he is in that region, but for him to get that production, it'll mean that he's getting such an enormous amount of ice time, that there's likely little coming in the sense of second hand scoring.
This said, I think we saw how good this team can be when that 1st line isn't necessarily clicking on all cylinders, but continually watched by the opposition's top defensive units, allowing primarily the Nielsen line to contribute. Throw in the nice little contributions that a combination of Grabner-Cizikas-Martin-McDonald were able to make and that full responsibility onus was no longer solely placed on the JT line.
What you rarely have is a first line with a 90 point, a 75 point and a 60 point guy in a situation where 4-6 more forwards are also chipping in 40+ points. We know what we think everyone is capable of under the right circumstances, but there's rarely the ice time necessary for ALL guys to be producing what they're capable of at the same time. For example, if Tavares is getting 90 points and say Cizikas gets around 30, then that probably means that Nielsen will only be hovering around 25-30 himself, as the ice time for the other two to get those stats - of which both are likely capable over 80+ games - has certainly infringed upon Nielsen's ice time and prime scoring situations.
Anything can ultimately happen, but this is generally what my experience tells me.
In the post above I did not mention what possibilities Grabner has. Basically, I see him as little more than an 'Ace in the hole' type of player. Incredibly incomplete, but a guy who will bite every now and again because he simply has the wheels to catch guys sleeping and a pokecheck that will take advantage of several players throughout a season. He'll get his 40+ breakaways over the course of 82 games. He may pot 15-20 of them, he may only pot 5, but he will get the opportunities. He does well shorthanded, so that keeps him from being too one dimensional, but otherwise he's lacking considerably in the all-round and physical department, even if he does have 10-15 brilliant passes in the course of a season. Thus, he's the statistical wildcard. Whereas it's easy for Cappy to cut his ice time when the going gets tough, Grabs'll get the opportunities necessary to be a 30+ goal guy. Unfortunately, he has the hands to only wind up with 10-15 instead.
Depending on what roles Regin and Clutterbuck etch out for themselves, Grabner could be anything from a 12-8-20 to a 30-20-50 guy.