Your scenario doesn't make sense. Team A doesn't fight B and C simultaneously. Team A fights A1. B fights b1, and so on. Team A wins 4-2, which means team A1 lost 2-4. That averages to a 1. You can't just take three random teams and toss numbers out like that. Every death is offset by a kill somewhere (barring suicides). Of course the KD or win/loss ratio won't work if you sample three random teams. That's like taking the Broncos and the Panthers and saying the average win ratio in the nfl is 12.5/1. The win/loss ratio in the nfl is... Wait for it... 1/1. Unless you count bullshit ties. Someone wins when someone loses. This is KD in a nutshell. So when you talk about the average of all players in destiny, it is 1. Again, slightly less for suicides.