If you have a word doc in a VS project and you double click it in Solution Explorer, it opens but is not automagically checked out like .cs files (annoying). The readonly bit stays, readonly (annoying)
If you check it out and double click you can edit it. If you save it and then go back to VS, you get the most annoyance, The Project xxxx has been modified outside the environment. Press reload to load the updated project from disk.
Where xxxx is the project where the word document is located.
Weird the document is not in a tab and you get a message to reload the project.