In my experience, spellcheck leaves a lot to be desired. Even on a finished document that I've manually verified as being perfect in terms of spelling and gramm

In my experience, spellcheck leaves a lot to be desired. Even on a finished document that I've manually verified as being perfect in terms of spelling and grammar, there's usually still a sea of red and green underlines offering incoherent suggestions in English as dictated by Google Translate. If the authors of the documents you mention are anything like me, we're so used to ignoring false positives that the net result now permits minor errors to slip through.