We have been on a good number of Princess cruises, another one coming up next month. Princess is a Carnival line as well as a number of others. EVERY time we sailed, a muster drill was held hours before departing. The drill is taken VERY serious by the crew we see. I must admit, I have a drink in my hand at the time:)
Last June on a cruise, while at anchor, the crew held life boat drills, lowering the boats in the water and actually practicing retrieving objects from the water.
The question I have is, are there different sets of rules and regs for the different brands Carnival owns?

This incident seems to be caused by one single captain who should not have had the position and a cruise line brand with less attention to safety than the parent company has on other brands.