I'm a lousy editor. And worse self-editor. It was even worse before I cut a lot of conversational background/why chat out, reducing size considerably. But I did intentionally leave in some why's. Without them, it would be here's how to set up calibre for new users step by step and follow my instructions and don't ask why each thing is important. Which I wanted to avoid - I'm really not trying to provide a manual. Just a map of what I'm doing with some examples. Examples in a structure of some reasoning help me learn better than examples not in some kind of bigger structure that makes sense.
Re nested spoilers, not to sound defensive, but I thought a flat 3 - 6 pages of text per high-level topic would have been potentially more intimidating to new user than another few buttons to press. (I'm aware of the python "philosophy" flat is better than nested.) I like pressing buttons, it's fun.
But I probably should go find a professional editor (edit: a human one I mean) - there are some on MR - and ask for a slash job. Any volunteers?