It might sound weird, but I think that the all or nothing approach mk is taking here is actually a natural way to do this for Hubski. Hubski is a place for thoughtful discussions, so the article is not the main thing to have quick access to. The discussion is. And you either want to keep up to date with the discussion or you don't. If this isn't what you expect of a save function, you can turn the notifications off and you have a save function which only saves the articles and not so much the discussions that follow.
This is my interpretation of the current save function, but only mk knows why he did what he did.