We have two systems, one for the old content and one for BC.
We have basically wiped dkp to start fresh with the new content but use the old dkp system as a 'tie breaker' system. Therefore, guildies who have been with us a long time and raided consistently will get the edge on a contested item (unless they're negative in the current system)
We're also stepping up dkp costs and rewards with each step up in content. This encourages people to spend their dkp rather than hord it for the next phase. Ultimatley, you want all your player geared up for the new content in order to be successful and rather than force gear on someone we simply made their 'credit' devalue in the next higher instance.
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