Word and Google Docs do save revision history, but they slow to a crawl when you have a document with a lot of pages, to the point of being unworkable.
In general, plain text is great because it's explicit. In contrast, word processors store some odd chain of objects. The steps to rebuild a document from scratch that leads to the same representation are not totally obvious. Sometimes it's a bit stochastic even!
XML formats improved the situation, but still plain text wins IMHO. With plain text you can have a toolchain where components for version control, edition and transformation can be replaced seamlessly. New stuff can be introduced at will. In e.g. Word you're mostly locked-in, or at least it's far from trivial to break out.
As much as I like vi's interface, I think emacs implementation is superior, and org-mode invaluable.
Why use org-mode as a format instead of Markdown? Internal cross-references. Org-mode feels just as light weight to me as Markdown for the most part, but it has fewer cases where you can't make things work. Worst case in org-mode, you mix in LaTeX.
Etc.
I think I still prefer to just write it in markdown. Word can't come close to the typesetting ability of LaTex.
I think the biggest difference there is that a document is "static". It is not supposed to process something else like code is.
Thus what you want to avoid at all costs is "boiler plate" bugs. Bugs that are not caught at compile time because it is semantically correct, but that end up producing wild results once a certain kind of data is introduced.
Microsoft Word's binary format (.doc) stored the document's text as a block in the file, making data recovery simple.
But version control tools are designed for code, i.e. showing which lines have been edited. With English text one would rather want to see which sentences have been edited. Are there tools for this? (Except MS Word's track changes feature.)
Well, one could write one sentence per one line, but that makes a pretty ugly txt document, when viewed raw.
Many of the tech writers I work with advocate exactly this.
In my stuff, I just hard line wrap the text. Diffs do tend to have more spurious whitespace changes because of this than I'd like, but that's still miles better than a completely opaque binary format like Word.
"Easy to edit," to take a phrase from your first link, is key.
:) I think you just made the case for bringing back the two spaces after a period rule!
Ha. You might be right.Not exactly sentence-level, but perhaps good enough for some...
Probably today I'd want to use Markdown, since I ended up doing something similar anyway to put in my footnotes as I was going. The worst part was always the hour or two of futzing around in Word to format everything for PDF export and printing, since it never came out quite the way it looked on the screen in Word 2003.
no crashes
can edit anywhere. even on a dumb phone.
revision control (i provided two scripts to the right click context menu to pull/push)
and the killer one: output to several standards. iso, abnt, eu-whatever... even automatic html formatting for the blog if a smaller article is not accepted anywhere.
though that happened before markdown et al became popular. so latex it is.
This makes me wonder how old you are ;-)