I’m not sure what that means. I just think you have to intentionally do it because once you begin in a thread under one name it defaults to that for your remaining posts.
You can use different names in each thread. But doing so intentionally in one thread to give the impression of being a different poster is not ok. People do it for various reasons, none of them nice.
Someone that was harassing me accidentally posted on another forum where they were a stalwart, using their new undercover name. I thought that was rather sad actually. They don’t seem to have returned since. After a decade of posting as a a seemingly normal person.