CEs were so well designed and fun that they certainly don't suffer from what cripples dungeon design. They certainly don't encourage tank turtling, they certainly don't count on healers to be there to raise each other or the people that chose to play DPS instead. They certainly don't reproduce the same boring boss arenas with the same boring twitchy memory mechanics.
But most of all CEs certainly don't break the game's display limits by shoving 72 players into the same cramped boss arena either.