Agreed. Not to keep with being off topic. But one method we try in our forum is to have the Op own their topic and deem if something is derailing it.
The muting, flagging system works okay to a point. The Script our member Kopa made improves upon the idea by having it hide posts in any topic from a user one finds irritating. Why the script would be a great add on as it improves the mute/ignore function.