How does Offline Editing of Docs, Sheets and Slides actually work?
When you edit dcos, sheets and slides offline, it doesn't mean those documents are actually in your google driver folder. Just as when you are editing online, your docs, sheets and slides on your hard drive are only a pointer.
So how does the Google Drive Chrome app edit them when you're disconnected from the internet?
It turns out that when you install the Google Drive Chrome app, and you've changed your Google Drive settings to allow offline editing, the Chrome app quietly places some secret files in a different place on your hard drive, which explains why it takes a few minutes to get it all working.
And you won't recognize them as your folders and files -- only the Chrome app recognizes them. To you, they will look like gibberish. That explains why you must run the Google Drive Chrome app to edit them when you're offline.
So, for the curious, here is where they actually are, and you can see the gibberish for yourself:
In Windows 7, they are located here:
Local\Google\Chrome\User Data\Default\File System
In Android, they are located here: