Nah 4k words should be fine, although I would still suggest spreading it out over a couple of posts in the same thread. Or at least use big bold
subtitles for the sections (if its possible). Just to delineate it a little, a 4k word block of text can be a little off-putting to readers.
Also if its a copy/paste from somewhere else it is ATS policy to just have a snippet and a link to the article/story. Instead of pasting in its
entirety.
The almight important factor of long textual threads, use paragraphs!!! Break up that text, it's easier on the eyes and you will be guaranteed more
people will take the time to read it.