Thanks James for the info on Luna's adventures. Looks like having a cat on board will result in flops into the water (unless you trapped her inside -- which I am unwilling to do). My conclusion is that I don't have the strong constitution you do to handle a cat's falls into the drink. I'd be a neurotic mess after the first time, much less multiple times. One positive note for me in your story is the apparent ability of a cat to swim around the boat and find a way back onboard (altho I wonder in a windy anchorage). I suppose I could attach some kind of extension to the swim ladder so a cat could easily re-board. I love to take one of our cats since I often do solo cruises on 3 to 5 days trips. The few times I did take a cat, it was a lot more fun having that company. BTW, as you know, one of nice advantages of a cat vs dog, on a boat, is that unlike the dog folks, who I see rowing to shore every morning and evening, cats don't need to go ashore.
P.S. Since you are basically a dog person, I am struck that you find cats more interesting than dogs. I certainly have always thought so too. As I say, I like dogs, but cats are my thing. True, a cat will never be your friend like a dog can be, but to me dogs are always doing the same things over and over again. They look at you with those big sad eyes making you feel special, or they run to you every time they see you, and those other doggy things; but with a cat, you never know what they are going to do next. They are always surprising me with some unexpected antic.