This might be a dumb question, but why isn't ROR - Reinhart - Larsson our three centers, considering they are the 3 clear possession drivers of the team? You'd then use:
Eichel and Moulson with ROR,
Ennis and Kane with Reinhart
Girgs and Gionta with Larsson.
Because we're not playing under Ted Nolan anymore.
By this I mean that we don't defend anymore the same way. Our defensive system is not anymore about defending your man, supressing shots and covering passing lanes.. (being a passive zone) We have moved towards a lot more aggressive, swarm type defensive system.
Basically defending is understood as covering your man and suppressing passing lanes. But that's not the bread and butter of modern, possession based defensive system. The point is not to wait for the opponent to make a mistake with the puck - the point is to break the possession before they have space and time to do anything.
And if you want to break the possession, you need to have all your defenders and your center to be able to get the puck carrier pinned against the boards, outmuscle your opponent, dig the puck, and be able to have the poise, speed and patiency to get a controlled zone-exit.
Neither of Reinhart or Larsson are exactly good at it atm. They are too weak and slow to be able to effectively break the possession, and they need legs and poise to be able to get controlled zone-entry WHILE BEING HEAVILY PRESSURED. And that is the reason most likely those two are not regularly played as centers atm.
Both of them are good at covering their man, positioning themselves and suppressing passing lanes. But you need more in a defensive system that wants to break the opponents possession as fast as possible.
Reinhart will get faster and stronger, and he has decent size. Larsson on the other hand most likely won't get clearly stronger, faster or bigger. He is a really good guy transitioning the puck when the puck is played to him after the opponent's possession has been broken. When he has the puck and is not under heavy pressure, he almost always makes a quick move that builds the play. But after now seeing how this team plays, I have little by little understood a bit more some of the decisions they have made.
Before the season started I also thought that Girgs should be a winger and Larsson a center. But I think I was just too used to watch a defensive system outdated. When you have watched the team being able to be possession wise dominant, and have seen how important role the breaking of the possession and getting a controlled zone-exit has, you emphasize more aspects than just being positionally sound and reading plays - which of course still matters a lot.