When I raided in EQ we used a dkp system, and it can lead to some issues, in regards to people "abusing" the system.
For example.
Say you were on a boss that only dropped mage useable items, and had 3 mages in the raid, classified as 1,2,3. The mages make their own "mage" chat channel. Mage 1 says " ok, I know 2 really needs the robe from xxxx, so lets let hime take it for min dkp, then 3 gets a turn, then me." Say the minimum bid is 10 dkp. When normally there would be a "bid war" going up to 100 dkp, it is now 10. So the next time a caster ring drops, 2 of the three mages have their normal dkp, while mage 2 has 90 extra to bid on.
Now, the problem with that example is that it's assuming that all raiders only think of themselves not the raid as a whole. Most good raiding guilds that I know of realize that the raid as a whole is better than each person, so that if uber ring drops and is better for their main tank, the others will bow out so he can get it.
I am a fan of dkp, but the thing is, it can always be manipulated. I was in a guild that used a modified dkp system, where all loot was assigned a value. If I bid on that item, if I had the most dkp it was mine, and the value of the item, in dkp, was deducted from my total. So if we had downed a guild first, the items would be high in value, thus giving a fair chance for all loot for everyone.
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