There have been a decent amount of Toronto AGM teams with the same trade being made, suggested by Leafs fans.


John Carlson (agrees to extension when the trade occurs)



JVR
Kasperi Kapanen
Kerby Rychel
Connor Carrick


My initial thoughts were that this is a bit of an overpayment by the Leafs. As a Caps fan, I watch Carlson a lot. I'm one of his biggest fans, but he's probably not worth all that, especially if JVR resigned with the Caps. But as I was thinking about it from the Leafs' perspective, it seems like all those pieces may be expendable. If they don't expect JVR to resign with them, he'd be expendable if it meant bringing a top pair RHD back. Carlson would be bumping Carrick, so he'd be expendable as well. Given the Leafs have a ton of forward prospects, they could take away from that to bring Carlson in. Losing Kapanen would hurt, but the Caps would need something they know would last coming back since JVR could walk.

What do the Leafs fans think about this trade?

This is most likely JVR's last season in Toronto so I don't have a major problem with him being traded, as you said both Carrick and Rychel are expendable, my issue with this trade is Kapanen. However these are my thoughts, JVR is one of the most underrated forwards in the league, the guy doesn't get the credit he deserves, especially since both are FA's next year Carlson in my opinion only holds slightly larger value. A fair various of this trade would be:


John Carlson


JVR
Connor Carrick
Kerby Rychel
Josh Leivo

If JVR were to walk as a UFA, the Caps would need more than just depth coming back. That's where Kapanen would most likely have to be included, so the Caps get something significant out of it. You'd have to give to get, and the Leafs won't be able to move their expendable pieces and get a top pairing RHD in return. Maclellan knows that, and would demand Kapanen unless JVR agrees to an extension upon the trade. Even if the Leafs gave Kapanen, it still seems like it works for both teams.

Kapanen is worth to much to give him up for Carlson. If I was going to trade Kasperi I'd go for an RHD of similar age.

I think I may have been the culprit behind this initial trade suggestion.
History:
I had been poking around Charting Hockey's Goals Against Replacement website looking at RHD with good GAR's who might be available. That's where I settled on Trouba and Carlson, although Carlson is more an offensive type vs the defensive shutdown type that Leafs most need. Tanev was a lesser option. Hainsey is just a temp 'lite' solution but fits the profile.
Then I read about the Caps and their cap situation and Carlson becoming a UFA.

So JVR was a one year rental to the Caps that they could either trade or keep depending on how they see theirplayoff chances at the deadline. Rychel was just a throw in since they might need low cost forwards and he can't make the Leafs.
Carrick was the carrot and a replacement on the RHD, 2nd or 3rd pair. I know Caps like him, he was drafted into their system and has good fancy stats. He's a loss to the Leafs but Carlson and Liljegren will help fill that side.
I still thought I was short on the trade value, given Carlson is a much valued and rare commodity: a RHD with top pair capability.
Now if Hamonic can get a first and two seconds and Hamonic to me is not close to top pair, then Carlson should be worth more.
At this stage, Leafs could throw in a pick but I think it would need to be a 1st round pick. So, since Leafs have an abundance of wingers and I hate giving up first round picks, I threw in Kapanen.
Leivo would be just OK to Caps, like a 2nd round pick. Kapanen could clinch the deal.

Sure, Leafs can start with a lesser package and see if Caps bite, whether its Leivo, Brooks, Neilsen, or whatever. I just showed the trade that I thought would get things done.

All this assumes that Carlson would agree to sign long-term with the Leafs and why wouldn't he want to sign with a rising high pace team that needs him on a top pair next to Rielly?