I don't think it is too harsh at all to remove insults, false accusations, words being put in mouths, and unnecessary snide comments. It's very difficult to moderate a debate form, because people do express themselves to the opposition with exactly what they think and a certain amount of freedom of speech should be allowed, but should also not be abused by the members for unnecessary nastiness.

So it's a fine line in allowing certain things to get across, but making sure it's to do with truth and what the topic is about also. Sometimes descriptions of people here in their behaviour can be accurate and necessary if that person thinks they are fooling everybody by veiled arrogance/insults themselves. But from there, it's really up to the moderator to say "enough, let's get back to the topic", or if someone has a posting history of non contribution to the forum, apart from causing or flaring up arguments/flaming/sarcasm, then they probably should be watched for more of the same and if it continues regardless of warning, then obviously banning that person maybe necessary.

But obviously it's not an enviable task. You'll always offend someone with your moderation, it's inevitable that someone will find it unfair. I think it's up to us members to try out best from here on it to do the best we can when answering someone's post and think before pushing send. Best not to answer in a heightened state of anger either. Though that maybe not be easy if the person has been strongly provoked.