I don't entirely disagree with onice here.
It all depend on the definition of a first liner. For many it all about points production for others, it all about how they're used (like me).
I'm not saying Patches isn't a first liner....yet, mainly cause he's stock with DD and that provide him with very sheltered ice-time.
For me, first liners are players you can throw on the ice against anybody and came out on top most of the time. DD's line are surgically used and are only on the ice with good ice-time and if they're not, they usually are dominated on the ice.
First liner can be thrown on D-zone start, O-zone start, against toughest opposition etc etc. That's really not the case of our so-called first line.
If we looked at ES time per game, it shouldn't surprise anybody that Patches and DD comes only at #96 and #97 for forwards in the NHL last season. That's pretty much why "onice" is saying that Patches isn't a first liner and he's right.
I would be happier with a Pacioretty scoring 30 goals and playing well in all game situations, than a 40 goals Pacioretty playing only in extremely sheltered ice-time.
Since Pacthes started to play some PK, i think he could prove to be a first liner....but not as long as he's playing with DD.