I believe thw inherent problem in this arguement is the nature of the CCC's.
No one complains when Sorcerers bring a dozen CCC's into a fight because that is the nature of thier profession.
Bards also have the ability to summon a considerable smaller number of CCC's, and mage-types can summon thier dragon.
These are all the result of player abilities, and are key to the fighting abilities of the skillsets.
City and Guild CCC's however, are not the product of such skills.
They are given special abilities such as the ones Allanon mentioned in order to make them a bit harder to kill and offer when they are alone.
Bringing them into battle is a sign that you are not able to fully compete in the fighting realm without help.
Do you think you will be able to drag Hecritor or Guathnamog or Prospero into a gem competition?
I do not claim to know the will of the gods, but in my memory I have seen a few gem battles and no CCCs were used that were not the product of player skills.
If you chose to use them, go for it, but keep in mind that relying on CCCs who are not under your control to summon at your request will, at some point be your undoing, as one day you may go to look for them, and find them riding the ship of death.
Written by my hand on the 7th of Springflower, in the year 999.