I look at it like this:
Imama and Martineau hits are very similar. Only difference, in my opinion, is the injury Imama caused.
When a hit like Imama's happens both teams and the players and medical info is all brought in the discussion.
Our argument against Imama is the obvious: charging, boarding, injury.
Saint John's argument: The injury is the only reason it's a suspendable offense and the 5 min penalty was enough.
The league's point of view is that the hit is dirty and the injury has to come into play.
Fast forward 1 game and you see the Martineau hit.
CB's argument: There's no injury, so should be no suspension.
SJ's argument: No different then Imama's hit, outside of the injury.
The leagues point of view is that the hit is dirty and the lack of injury means fewer games.
Say what you will but SJ's management and veteran coaching did exactly what they were supposed to do: influence a future decision based on a past ruling.
I honestly see the hit and see the same hit minus the injury to Bisson. From that simple perspective, 4 games vs 7 means the league actually got to fight back against SJ's argument that they were only penalizing the hit.
Martineau's actually being punished in an attempt for the league to show SJ that Imama's hit was just as dirty and that the injury only played a small role in the amount of games given. Add in the hit, repeat offender status, and the injury and the league argues they only gave an extra 1 or 2 games to Imama for the injury to Bisson.