As a person who has been visiting WDW for over 20 years and has ridden Pirates are more times than I can count, I have to say that a sign isn't going to do diddly for me. I've ridden Pirates before and gotten splashed here and there. If I saw a sign that said I might get wet, I'd think that someone who got splashed complained because they were hoping to get something for free and managements solution was to put up a sign. I would not think that the ride suddenly changed to where I was going to have a Splash Mountain experience. I'd have to see something on the sign that stated something to the tune of, "Due to recent changes in attraction equipment, please be prepared to get wet or possibly even soaked while riding Pirates of the Caribbean." I'd need to see that changes to the ride had been made before I thought that I actually had a chance of getting more than a little splash.