If you think being 100% correct and precise in your instruction manuals will guarantee people will not fuck up using your system, sit down with someone reading your manual sometime to be cured of that notion.
First thing I noticed is that people don't read manuals like novels. They will open your manual in the middle, browse for things that stand out as something they know already, and do that first, regardless of your manual listing 40 steps that need to be done beforehand.
@peterdrake
ROFL Figures M*A*S*H had a scene for that.