I'm assuming this can't be done because i can't see anything related in the help files or on this forum.
If you have a website owner, as a lead moderator and 4 other collaborators all making changes. It would be great to approve or decline changes.
As an extension of that, to publish only specific users changes. If you have 4 users all logged in and some users are making quick changes and want to get them published quickly, and other users are making extensive changes, you have to wait until all other collaborators are done and then publish everyones changes all at once.
Also as an extension of that, if you make 20 changes and then at the end realise you made a mistake on change 2....there's no way of going back to that specific change and saying 'ignore' or cancel. You have to remember what you did and change it back.