First of all, I have serious doubts that you are familiar with what motivated Bertuzzi, though you may be well acquainted with the assault itself. It in no ways justifies what he did, but know that he didn't just decide one day to go break someone's neck for kicks.
Two, Onizuka, he was actually a good player before the incident, but his spirit seems completely broken afterwards. Judging from his play, the news reports, and first hand reports from friends who've met with him (went to dinner with him, actually), he's pretty depressed and isn't into the game anymore. He's beaten himself up psychologically quite a bit after the incident, so know that he isn't sitting around grinning about what happened.
Bertuzzi has no confidence anymore, and in a way, he is just an obstacle now. Though some like to cling to the memory of the player he used to be, nowadays he skates lazily around, he hardly ever seems to put on a burst of extra speed. Naslund is tired of the game, and Morrison was never great, just good, though he hasn't done terribly well, so Vancouver's top line is gone, and sometimes I wonder if Bertuzzi deserves to be on the team, and that we should trade him off for some defensive spark. But no one will take him but Vancouver, and he is a good player when he wants to be (game I went to vs. Detroit I think, scored a hat trick). And when I hear the boos he gets and the hatred he's receiving, I want him to get through it, because with so many people thinking he's just a big talentless mean-spirited brute with nothing to contribute to the play, at least some have to remember how he can play and what led him to do such a despicable act. And again, in no way is what he did ever justified, but given the chance to go back to that moment, I doubt Bertuzzi would do it again. Hockey's a violent sport, there's fights and there's cheap shots everywhere. Bertuzzi wanted some revenge, wanted a fight with Moore, and Moore was smart enough to stay away from him, but Bertuzzi's too much of an stupid emotional idiot to just calm down. And what Bertuzzi did was a mistake, and that mistake has cost him much. It does not equal the loss that Moore suffered, I was among those who supported Bertuzzi's suspension until Moore was able to play again. And I would be among those crying for more punishment for Bertuzzi if I hadn't followed him and known him like I did in the years before, known why he acted like he did, and heard how his spirit had completely broken. I may not entirely forgive Bertuzzi for his absolute idiocy and his absolutely despicable violence, but I forgive him enough to let him be, without booing him and denying him the opportunity to rebuild himself.
