As far as Guerrilla goes, at one time, yes, they were a dominant guild. That being said, they did still lose to pugs occasionally and other guild premades, but for the most part they didn't talk a ton of ****. Eventually most of their good players abandoned server, which left us with a watered down (at best) version of the guild which was pretty much just back pedallers and keyboard turners who continued riding on the Guerrilla bandwagon despite their incompetence. Some of these players who were left behind still linger around, and still spout off about how Guerrilla was the best thing to ever happen to this server at the mere mention of the name.... And this is why almost no players who were around when Guerrilla was actually good will give it a shred of respect, because the dregs that were leftover when most of them left ruined their reputation for everyone.
^ heard that said verbatim more times than I would care to count