So I edited an answer originally by P-Nuts by adding four carriage returns, since the answer was a big wall of text and I wanted to break it up with paragraphs. But SO says after the edit that I did 60% of the answer and marked me as the owner of the answer.
This is the answer that I edited: http://stackoverflow.com/questions/2079335/experience-programming-with-netbooks-in-daily-commute/2079397#2079397
I believe there is something wrong with your diff algorithm. Since the change was only four characters long out of 803 characters. The change should be of 0.5% rather than 60%. It seems like SO thinks I removed 60% of the characters (which would be after the first carriage return) and replaced all of it.