I was on a Sun Princess cruise when we lost power for about 5 hours. There was no fire, simply a power outage. Communication from the Bridge was prompt and calm and informative.
The most crucial job was getting people out of elevators who had been in them when the power went out. Also, people using wheelchairs could not navigate stairs.
Buffets were set up in the Atrium on every deck. I saw tiny, young crew girls carrying a case of water on each shoulder, hurrying to serve people. The crew was outstanding, as I suspect they were on the Triumph. We had our share of rude, obnoxious passengers, who hoarded, cheated, took "cuts", complained loudly. They acted as if Princess had staged this just to annoy THEM.
Yes, my friends and I had some "what if" discussions, but we remained calm and thought out our plans and acted like polite adults. Toilets were somewhat working in cabins, but the crew told us where we could "go". My cabin steward held a flashlight (with his back turned) so that I could find a sweatshirt and some pants to keep warm.
I'm sure there will be lawsuits galore about this cruise, but no one got seriously injured or died. Life is full of risks - hell, it's a crapshoot from the moment you're born! I trust that Carnival will be as fair and accommodating as Princess was to me and other passengers. They did not will this, ask for it, so I have no sympathy for those who would blacken their name.
I do hope that crewmembers will receive some sort of extra compensation for their efforts, which I'm sure were "over and above".