Slave Nano is discussing the editing process for what sounds like a pretty extreme bdsm novel, Adventures in Fetishland (a book with some inspiration from Alice in Wonderland):
Adventures in Fetishland has scenes of corporal punishment, nipple torture, cock and ball torture, electrical play, medical play, use of sounds, strap-on-play, cling film mummification, breath play and an attempted anal rape scene. So, you can see, it isn’t exactly for the faint hearted! But, one of the scenes I had to edit was a comic one involving Kim, the main character, pissing in a tea pot! I just have trouble grappling with how all that other extreme stuff was acceptable but a funny scene at a fetish hatter’s tea party involving pee had to be axed.
I take that point. The aversion to pee sounds silly in the context Slave Nano lists. That definitely got me thinking.
On the other hand, I wonder how salable watersports writing is. Does the publisher have any stats on that? My personal reaction might support the publisher's decision. I like some extreme stuff, and when I read the list of what is in the book, I get a little excited. Maybe a lot excited. Watersports, on the other hand, is icky to me a lot of the time -- I have read some writing about it that I liked, but it's often a negative in a piece of writing I otherwise love.
I think it's worth examining the reasons for avoiding certain subjects, and, every now and then, experimenting with pushing a boundary or two. If you're ready to push a boundary now, Slave Nano's post includes an unexpurgated version of the pee scene he had to cut from the finished book, and it is in fact quite funny.