I agree. In my experience, a mod who communicates with the room as a whole in open chat is the quickest and most effective. I've seen a mod defuse rancor in an instant and a new topic begin with all members behaving appropriately. It is simple, sensible, and fast. Members listen to moderators in the chat room when they direct us. No feelings hurt when it is addressed to the open chat room to all the chat room members, not pointing out anyone, just pointing to the topic.