One way I am thinking of using CC in dungeons will be
/Target tank
/cast [target=targettarget] Hex

What this will do is cast the hex on whatever the tanks current target is, all you would need is this macro assigned to a different key and keybind for the toons you want to use CC on.

My other dungeon CC thought is, using ISBoxer and a click region I can assign all my toons a target to CC flipping between each of their windows and then click one button to iniatiate their CC spell and so all mobs would be CC similtaneously. This obviously will not work if you are running toons across multiple machines