It's true that I initially didn't know about this difference in conventions, but neither did heyuhua; I had to find it out all by myself. heyuhua didn't correct this for many, many posts, so it's a bit disingenuous of you to solely blame me for it. Also, please refer to post #650, where somebody from the moderation staff evaluates my contributions in this thread. I suggest you take your difference in interpretation as to what is trolling up with the moderation staff. And perhaps you should read the rest of the thread, where it becomes quite clear that Yang still changes the sign; heyuhua explicitly mentions this multiple times. So it's not 8 versus 4, it's -8 versus 4. Perhaps it's not me that should "stop trolling on this point", but you that needs to start paying attention on this point.