To those that think it wasn't self defense:
Why do you think he hit Stafford, then? Do you actually think he said in his head, "Hmm, I don't like this Stafford guy, so I'll swing my stick at him."
It was indeed self-defense. Stafford did almost take Perez' head off before. Perez just reacted to it badly. He doesn't have a history of this sort of thing, so obviously it wasn't intentional. A year was a joke as it is.
Technically, the NHL cannot likely suspend Perezhogin. He was suspended in an entirely different league. The NHL will probably have no grounds for keeping the year suspension intact, so Perezhogin will play in the NHL if he makes the team and there is an NHL season.
On the Labarbera thing, he was suspended a couple of games, so he and the Rangers organization probably didn't care. But this is a year suspension we're talking about. Bob Gainey has probably been looking into it since the incident occured.
And for those that would lose respect for Perez if he escaped the rules: how would you like it if someone nearly took your head off, you retaliated, and had to go the year without hockey? The guy just wants to play, and since he's found a loop-hole, he deserves to play. If he didn't make the team, or needed confidence, you may see Gainey and Perez restructure the contract to make it a three-way(unless he doesn't need the three-way option) so he can go to the ECHL, which would be escaping the rules once again.
They've found a loophole. As much as you may not like it, they're just trying to not waste this guy's year, and they've figured out how. Good for them.