Okay there is something you’re really not grasping here - top nine and fourth line are different. It isn’t just, “hey go get the 12 most talented forwards!” Fourth liners are asked to do different things.

These include:
Penalty kill
Physical play
Intense attention to defensive structure
Shot blocking
Energy

If a guy can’t do those things, he’s not a fourth liner in boston. Can’t do the job.

So sounds like you think he’s better than Trent frederic - why? Is it just because he’s a flyer? Is it because he’s a recognizable name? When compared to Frederic JVR is:
Not as physical
Not as fast
worse defensively
Scores less at 5 on 5

Where’s the benefit to boston?