One thing I have found helpful is to always maintain the mindset that my pet is my enemy not my friend, and my main purpose is to mind-screw and create chaos, weakness and death among the opposing ranks. One thing I aim for is to have all of the enemy die, including and especially my pet. This is the big difference between necro pets and coercer pets IMHO: one is strengthened and nurtured and one is weakened and destroyed. I consider a perfect round one in which both pet and opponent die simultaneously. I also keep a big nuke "in the chamber" for the killing strike when my pet is finished with his job and has a bit of life left. For a Coercer I think the term "pet" is an unfortunate choice of words. One thing I do for my group is pit the enemies against each other so that when we take them on they are that much closer to death, so having the party kill your pet is the desired end. Many times in an encounter you can find the "off" mob by tabbing through them and mezzing the ones that have a full health bar or are targeting the healer, again creating chaos and weakness among the opponent. I don't consider it as important to keep any one target mezzed as it is to take off targets out of the action while no one is fighting them. The recast timers are short enough that you just move on to a new one if your party start hitting the one you had mezzed.