I would say rumble K/D is a good example of how K/D does NOT determine skill. The game mode encourages you to force encounters and you are not penalized for deaths. For example, if I play agressivly and force 30 encounters, and I win 2/3s of them, I will get 20 kills with a 2.0 K/D. This may win me the match. But if I play conservatively, and only force 20 encounters, and win 3/4 of them, I will get 15 kills with a K/D of 3.0. In this case, and many others, the guy with the LOWER K/D is acually the superior player.