I quite like how it encourages me to slow down and take my time as well. I think in the time one has to review other people's comments a person could either calm down considerably (and maybe re-think their comment if it isn't particularly civil) or out of frustration choose not to comment at all. It's like the rating system adds a second layer of screening by default as people who are riled up and looking for a fight will choose not to use the system.