Whether on SF or not, in my experience, the best way to ruin your online day is last-worditis. For obvious reasons, only one person can have the last word on a topic, and when two sufferers of last-worditis collide, the result is an endless stream of increasingly more antagonistic posts. Last-worditis is fueled by a condition I call "error intolerance". People cannot see something they consider wrong without commenting on it, possibly because they feel their silence would be interpreted as affirmation. While this 'affliction' basically is the secret behind Wikipedia's success, in a forum such as this, it naturally leads to last-worditis. For those suffering from last-worditis, the practice of not commenting on something one perceives as blatantly wrong, and letting an opponent have the last word may feel awkward at first, but is ultimately immensely liberating. Try it. Paging TS.