Depends on how good Blackwell actually is. If he actually has the skill to play with good players and put up 15-20/40, and competes every shift, thats is kind of what that line needs.

Blackwell is a 4th liner who could play on your 3rd in a pinch. not sure he's good enough to play with the likes of JT and Willy.
Why? If you just flip Marner and Nylander.It has sucked for a while now, but I don't see any option better than Nylander & Tavares figuring their shit out together. Splitting them up will also lead to us playing the Mikky-Kampf-Engvall line less, and those 3 are ridiculous together.
Why? If you just flip Marner and Nylander.
To me, it has looked like he's got a conditioning problem or an illness (mono or some shit). He's sluggish. He gets a little jolt when he's got some open space around the goal, but other than that, he's just struggling to move out there.Nylander has to have a nagging injury or something - he's not skating as well, and his puck-handling has been sub-par. I don't think its a confidence/consistency thing, I think he's battling something.
I don't remember that. I feel like every time Marner and Tavares are together, they're great. Tavares's first year here, Marner helped him almost hit 50 goals.Bunting-Matthews-Marner might be the best line in the world, I don't see the point in fucking with it. I'm also not convince that Marner fixes whatever is wrong the JT's line. The last time we saw JT & Mitch together for an extended period, we were frustrated by them (not too dissimilar from how we're frustrated by JT & Willy at the moment).