My wife was working on a Word document in Word 2011. She moved the document, saved this morning at work, from Dropbox to another folder on her hard drive. Then she worked on it this evening in Word for a couple of hours. Everything seemed normal. Typing, deleting, etc. looked normal on the monitor. Word was set to autosave every 10 minutes (the default).
Then Word hung up, and she had to force quit.
Then there was nothing to recover. Word had apparently been malfunctioning and not saving for two hours. Nothing in recents. Nothing in Time Machine (even though it had saved during that time). No files of the name of the one she was working on, no .asd files (the suffix for Word automatic save documents).
Here's the official Microsoft statement about Autosave:
Amen to that. (Actually, I'd amend to say saving manually is the only way to preserve the work you have done.)The AutoRecover and AutoSave features are not a substitute for regularly saving your work by clicking Save Button image. Manually saving your file is the surest way to preserve the work you have done.
The only way I can imagine to deal with this is to manually save (or use a macro app like Keyboard Maestro to trigger command S every few minutes) and/or to save the document with a new name regularly.
* I used to work as a writer. I had to use Word, as all my editors did. Word, from version 6 - 2011 crashed on spell check as a normal course of events. It crashed at random times even when I wasn't spell checking. I regularly lost work, even though I auto saved every 5 minutes, and saved dozens of named versions of every document.