Jarnkrok isn't a center, he's actually been on Johansen's wing most of the season. He's having probably his best season as well.
The third line is Grimaldi - Bonino - Smith, which benefits from Grimaldi's speed, Smith's defense and Bonino's willingness to go to the net.
As good as that third line has been, Laviolette split them up last night along with the Blackwell - Sissons - Watson line, to spread their hustle and work ethic throughout the lineup. The Preds scored 8 goals.
One thing that has hurt the Preds top-6 this season is injuries. Forsberg, Granlund, Arvidsson and Duchene have all missed games to injury.
Duchene hasn't really been allowed to gel with anyone yet even though his talent is obvious, game after game he is making plays but has no finisher on his line. At the beginning of the season he scored well when paired with Forsberg and Granlund, but then the injuries started and his line has been in a blender ever since.
Johansen, seems to be a case of work ethic. He can take over a game when he's got some fire in his belly, but it seems like he's content to coast through large portions of the regular season. I think he suffers from missing Arvidsson more than anything, Johansen thrived on playing a responsible game in his own end and collecting assists by springing Arvidsson for breakaways.
The Preds lack of top-6 scoring is a major reason for their standing at the moment. The bottom-6 playing well is great, but not enough to carry the team alone. Not with the inconsistent defense and goaltending that we've gotten.
But I think moreso than just injury and lazy play, what it really boils down to, is the continued failure of the Predators powerplay. It's been more than a full year of a truly awful powerplay that the coaching staff cannot figure out. And not scoring on their advantage opportunities is sucking a lot of points off of the top-6 totals.