Well, still looking at the random dungeon finder feature.

If you are randomly assigned a group like this:
Paladin - Tank
Shaman - Healer
Rogue - DPS
DK - DPS
Mage - DPS

That gets you, Hex from the shammy, Sap from the rogue, and maybe kite one mob with the DK.
The cooldown on Hex won't allow you to re-Hex once it breaks.
Sap requires the target to be out of combat, so it cannot be applied either.
A rogue could re-CC via Blind once, I suppose.

But this group could easily occur with the dungeon finder.
If you were in an instance with demon type trash, there aren't a lot of CC options.
If CC is basically going to be a requirement, then the dungeon finder needs to change how it builds groups.



From a boxing point of view.
We can create macros for /Cast [target=Focus] CC-Ability.
We can round-robin, via software, our Focus targets.
We can raid symbol mark our Focus targets, via the class that is focusing, to visually be sure each Focuses the correct target.

We're not likely going to be able to kite a mob, with a Hunter/DK, while playing the tank, healer and other DPS.
Our option will be the initial CC as the pull is made.

Depending on the difficulty of mobs... If they're as hard as heroics were in the early BC era, prior to SSC/TK, we might only be able to do 5-mans with mixed groups - ie, a large number of different CC modes.
But if the mobs just hit hard and are otherwise nasty but doable, then frequent eating/drinking - possibly between every pull - might be enough.