After going through the COHO and Kassian threads the dominant rationale among the crowd that likes this trade to bring in Kassian is that he brings an element of "toughness" to the line-up that we didn't previously have, and that COHO didn't have a spot behind Kes and Hank moving into the future.
Fair enough COHO ain't exact 6,3 230! However i think these arguments are in many ways flawed.
The leading hitter on the Canucks is Lappy. He has 178 hits in 63 games. or 2.83 hits per game, averaging just over 11 TOI per game. He also has 7 fighting majors, scrapping in just over 11% of all games this year. He has 118PIM averaging 1.87pim/gm
Zach Kassian on the other hand has 39 hits in 27 games or 1.44 hits per game, averaging 12 TOI per game, he has 2 fighting majors, fighting just 7.5% of all games this year and has accumulated 20PIM averaging 0.74PIM/gm
TL:DR all of it.
Your logic is flawed however if you think Kassian was brought in to be a 3rd line grinder/hitter.
Like a Bertuzzi hes an offense first, physical second guy.
He will look for the goal/pass first unlike Lappierre.