The need for CC is really only there if your group has a bad tank or a bad healer. If you have a good tank and a good healer CC isn't necessary (I can't vouch for dungeons in the 30+ level range though) because stuff will be controlled by only attacking the tank and the healer will keep him alive, therefore making CC unnecessary.
CC is always helpful though, I've seen Bards and Druids who put casters/ healers to sleep during a run and things went much more smoothly...but the situation was by no means unmanageable without the CC, it was just more difficult.
I am not sure who does CC the best, I know Druids have a sleep spell, Bards do as well, but I hear Dominators do really well.
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