Yes, that move was a clear fail.
Sami Pahlsson was an absolute disaster. "A legitimate shut down guy" - sure, if you're talking about the year 2007. He was not shutting anybody down on Columbus. He's a guy that had one foot into retirement since going to the BJs, and I would venture a guess that he wasn't too happy about being traded to the Canucks. He really added no value to our team, the 3rd line was no longer a scoring threat whatsoever, and opponents no longer had to concern themselves with 3 lines - just the top two.
Why wouldn't he be? even if he did have one foot into retirement/going to Europe, why wouldn't he want to have atleast one more legitimate shot at Lord Stanley while he is still here and able. He's still making the same money? It doesn't make sense.
Trading Hodgson for Kassian was a reasonable gamble to take, but the timing made no sense at all. Hodgson is clearly the better player today, and (IMO) likely will be over the course of their careers. For a Cup contending team, why on earth would you trade your 3rd leading goal scorer for a guy who's not even close to being at that stage of development, heading into the playoffs? If Kassian was available at the deadline, there's no reason to think that he also wouldn't be available at the draft, so, yes, this was a timing error on Mike Gillis' part.
Hodgson didn't want to be here, they had probably been trying to trade him sooner.
The Timing did make sense if you look at it like this:
They wanted to get a young player in return that was about at the same level as him, and as Gillis said, none that he would have traded Coho for were ever made avaliable, except Kassian, and how do you know he was avaliable right away. A prospect like that, I doubt he was made avaliable right there, Buffalo probably offered less, but at the end of the day they saw there major need for centermen, and stepped up and paid the price it would take in Kass. That would also explain why it took place later in the day. Then it also worked out timing wise that we were able to pick up another center, after all Gillis and the managment said they didn't feel our center ice position was strong enough coming into the day, so that is before they traded Coho.
Also Pahlsson did better than you give him credit for, he wasn't great in the playoffs but he was better than what Manny would have brought IMO and who wasn't bad in that series.