I think its based on the skill level of the people you kill. The higher their skill, it goes up, and if you get killed my lower skilled people, it goes down. Like Udgnim, I mostly played Domination in the beta, which is why I think our skill is higher. You run into the same people over and over, so constantly going 1:1 or higher against high kd people increases your skill more than the occasional noob getting a lucky kill decreases it. I copuple of times I played against youtubers like xfactor and did fairly well. My KD is fairly average in the beta, 1.3 ish, was almost 2 then dropped when I switched from assault to unlock other classes stuff and I played a few hours of conquest. Frickin tanks. Anyways, thats the only thing I can think to explain it. My spm and skill stats are similar in BF3, and the last hundred hours or so I only played metro and/or infantry only.