I was on Prexus. I actually believe it was due to new content like POP and smaller groups able to kill bigger things. Pharming Hate and Fear for gems with a single group etc.
I did experience alot of tense moments with some of the Luclin raid events. A couple of times other guilds sent in a breaker to agro and wipe the raid then another guild moved in and assumed control of the raid. Without proof, little could be done about it. It really sucked. The guild I was in spent so much time getting everyone keyed for the Shissar and we got into the rotation. I.E. No one appeared to be interested in this mob at the time. Or so we thought. Another guild showed up after us and while we were buffing and clearing trash they sent in an untagged breaker and people started getting summoned, deaded, it was nasty. Took several hours to clean up. All our work on keying and have it end like that. Was tough.
I'm not quite understanding keeping a lock on a specific mob rotation though. If there are X number of guilds capable of doing the mob, x number of guilds should get a shot at it. Keeping it locked by fanning out keys to random people or destroying them seems pretty weak.