Yes, the button limit was very annoying.  This only affects the unscrobble button when the movie is partially watched, because that is the case that it shows both the scrobble and unscrobble buttons normally.  With RT enabled and this change, you'd just have to mark it as watched first, and then would have the option to mark it as unwatched.

I'm not in love with the solution but it was a fairly clean way to fix it.