I think you can wear anything but a thong (and maybe they don't say anything about those either). I could not believe what people wore in the parks, let alone the pools. Many gals were wearing t-shirts with out bras coming off the water raft in Animal Kingdom, and we saw them through out the day..and they still were see through..and judging by a few remarks we overheard from some male CM's..it was well enjoyed. Some guys had no shirts on in all 4 parks..and many, many gals were wearing either just bikini tops, or a few just bras (or they found see through bikini tops that look and adjust like bras), with the skimpiest shorts I've ever seen (and of course many of their thongs showed as they walked through the parks (both because of light colors that got wet, or light colors with dark thongs, or because the top of the thongs were higher than the top of the shorts)...and some of the shorts were cut so low, I guess the razor got a work out! So dont' worry about the pools.
I was feeling very old this past week LOL!