Golly, i sure suck at multiplayer. Doesn't help that Markmad1 repeatedly kicked my ass recently, which resulted in a notable drop in my win ratio. Also, got Band-Aid achievement that day.
The dreaded Qi bug some time ago took me from green belt to blue belt, all the matches being wins. In reality, it'd be more like 1,5-2 instead of 3,6. Also, it was 4,2 before Markmad. That's a 0,6 point drop in one hour. Beat that.