Actually, I've used (regular) T_EX for documentation long ago. I'm aware at how powerful a separate formatting pass, as opposed to WYSIWYG, can be. The obverse side of WYSIWYG is What You See Is All You Got.

I got a LaTeX book once, but didn't care for it.

Once upon a time, I decided I'd rather have copious documentation rather than beautiful documentation, and used Word for the project. It's just so much easier to create and edit, esp. if inserting illustrations and such.