Why even bother, really?
I rage.
Going in as a random in reach, checking the kd's of players on the opposing team usually tells me how hard I have to try to secure a win. I always assume everyone on my team has a negative kd, more often than not that is the case.
Suppose someone has more double kills than games in a playlist with triple kills approximately 1/10(or greater) of that, and has a kd>=1.5, it would be a safe assumption that they are better than the majority of the players in the said playlist(Excluding BTB, multi and LD).
[Edited on 03.21.2012 7:57 AM PDT]