I am assuming that "piss" in 17th-century English was a purely innocuous word, unlike today when it is seen by many as being slightly vulgar.
As far as sitting down, I might do it, if it's in the middle of the night, and if I'm awoken by the urge but too sleepy to stand up when I could sit, but aside from that, it smacks of something invented by women to denature men and make them more feminine. There's a certain stripe of woman who will do that, and that is the kind of woman that no man needs to bother with.