[techiferous]

"Don't be a jerk."

If you read his comment carefully you will see that he simply stated a fact. Stating a fact is not being a jerk. However, by saying "don't be a jerk" you've added a personal insult to the conversation.

Tone is really hard to convey on the Internet and I also hope you don't misread the tone of this comment. I'm writing this in the spirit of a friendly reminder that I myself need sometimes, too.