If your tank is pretty standard on his pull timing, you can get Despotic Mind on you and one other person with enough time to trigger it and it will be refreshed and ready to cast again very quickly into the encounter. I set up two Despotic Mind macros - one with my name and one with the name of a mage (or if no other mage, a bard) on the second. I hit myself first because I've found that most enchanters are twitchier than other mages (must be the fast cast speeds that make us twitchy!) and then when it repops I cast it on my mage friend. Once into the encounter, I only cast it on myself.
That only works on slower pull cycles, raids or tougher heroic content, where you tank isn't immediately pulling the next encounter. On a fast burn instance, I try as much as possible to pre-cast mind on myself so that I can get those triggers off and immediately have it available to cast on myself again, and don't put it on anyone else.
Have to be careful though about aggro - I cast it once on our warlock right before an encounter in VP, and on myself as well. Opened with lash, we both started AE nuking, I was dead really fast. Spiked up to over 10k DPS though before I died!