I have read a lot of Boston posters talk about need for more grit and size and Kassian is a good player in that role. The issue with the Oilers is we are short of qualified top 9 players, so need more offence out of him than he is capable of. Bos doesn't need him to score goals as they have a well balanced attack already in place. I think Debrusk has more value than other Oiler posters and know Kassian by himself needs to have an decent asset attached. My opinion is the Bruins can fill Debrusk's spot with Yamamoto and not miss a beat. Kassian can step into the enforcer role and still be a valuable contributing player. I feel that this deal would improve the Bruins team for playoffs because they may be swimming in shark(Wilson) infested waters. The real question would be in this discussion would be "would the Bruins Qualify Debrusk if there is not a value trade offered?"
For the Oilers this deal is a gamble given the cliff that Debrusk walked off since the pandemic started. He has a huge qualifying offer in a year where they need to sign Puljujarvi and a netminder. This by itself is why most Oiler fans have been against this deal. Yamo would be cheap to qualify and he is popular with his teammates. There is also the dynamic of this appearing to be an OLD BOYS CLUB kind of move with the link to Ex oiler Louis Debrusk. Taking all that into consideration the upside on this deal is worth the risk if for no other reason than you clear up Kassian's term. Paying Yamamoto to get rid of Kassian is disguised by "adding a top Six forward for the playoff run". The truth is we are paying to get rid of Kassian and buying an expensive all or nothing lottery ticket. The word from one of the oiler reporters is all deal have to be money in money out which this does.
There's a big difference between Bruins posters here and the team's coaches and front office. The Bruins simply do not value size at all. They want token grit, but they've been burned every time they've tried to acquire it.
I've always liked Kassian, personally. I've wished the Bruins could get him for years, but he's always made too much money for it to ever make sense. That's still the case today, and he's getting to that age where he's gone from overpriced to hot potato. I don't see any way the Bruins would view him as any kind of positive asset.
I won't say your idea is meritless, but Yamamoto is basically what I'd be looking for to accept the $8m contractual obligation Kassian represents.
I'd also say you're viewing DeBrusk in too much of a black/white perspective. If he's a half year rental, it'll be because he's still struggling and nobody will care he's not qualified. If he turns it around and plays like he did this afternoon, well, QOs get talked about loads around here but the players nearly always go for more security than a one year deal offers. Given the Oilers' cap outlays, maybe that's more of a worry next summer, but he's a local with family ties, and despite Bruins fans dumping on him constantly, he's never been surly or disruptive. I suppose the worst spot they could be in would be if he's too good to non-qualify and still worth less than $4m. Tough if you're strapped that tight, but it isn't Holland's first rodeo.