Before you complain, be sure it is something within Carnival's control.
Brad, I'm sure that Guest Relations are accustomed to getting complaints about how crummy the weather was in Grand Cayman, or how much the perfume cost at the vendors in Cozumel, or how they could feel the ship moving, while underway, on the way to San Juan. It's amazing what some people will complain about!
That doesn't mean that someone should make an unreasonable complaint.
In customer service there is no such thing as an unreasonable complaint, there may however be a situation where all the compenstaion you get is " I am so sorry for that experience , your business is very important to us... please sail again!"
Something about the travel industry I know all too well. If those that find something to complain about can't get a response from the cruise line they often will sue their travel agent, which is why any decent travel agent has some sort of Errors & Omissions policy, which is basically the travel agent equivalent of malpractice insurance.
Not only in the travel business do you get people that no matter what you do they will always find something to complain about. I'm in auto sales and you can treat someone like the King and they still aren't happy. You just have to smile and not let them get to you. Kill them with Kindness.
Monarch of the Seas 3-92
Celebrity Century 7-96
Dawn Princess 2-97
Enchantment of the Seas 11-98
Rhapsody of the Seas 8-99
CCL Inspiration 8-08, 8-11
CCL Valor 1-09
CCL Glory 11-09