Collaborative Editing

When editing a document in collaboration with other people, each one has a paragraph locked (marked in their own color). Other people are not able to edit a paragraph while other is working on it. I think that the background color is quite good to know where other people is editing, but there should be the chance to edit the same paragraph at the same time.
It is more relevant when the main author starts the document from copy&paste, because no one can edit it later if the author does not break it in different parts.

I think it would be better if there were the possibility for others to manually break a part of a locked region not being used by the actual editor.
alexorbis