I saw a lot of that in my guild, as well. We were one of the further progressed guilds on a somewhat backwater server, and the poaching rates of geared tanks and healers was pretty extreme. With a limited talent pool you'd also see a lot of yo-yo players - they'd leave for greener or more lucrative pastures, find out they weren't on easy street insofar as drops were concerned, and then come back and try to act as if nothing had happened. Lots of distrust, recrimination, and overall drama - and that was before M'uru broke the spine of the guild and gave our raid leader a nervous breakdown.