15000 characters, not words. That are about 10 "standard pages", which equals ( from my experience) roughly 2500 words in the german language, probably a bit more in the english language (because of shorter words), but certainly less than 4000 words.
So definitly not one of your chapers, but still quite a big chunk for something that is supposed to be "bite sized", that's true ^^
On another note: The Bold and Italic are quite important and helpful tools for writting. I'm looking forward to what comes next, but the current set of tools seems sufficient for the basic writing of any kind at the moment ^^