Google Docs Idea

I was just talking about google docs with a teacher here at school and he had a great idea for using it without group work. He was saying that he could have students writing papers and collaborating with him, that way when they were finished with the rough draft he could add comments. I think that would work well. The students could write their paper, he can edit that part, they can then go back to make revisions, turn it back in, and so on...