@emerson1975Where did I write something about a K/D < 1 (I guess this is what you mean by negative?).
I wrote that "K/D is a bad indicator to detect cheaters -- if taken on its own".
Of course the K/D of cheaters is better than it would be if they were not cheating. But I have seem clear cheaters (wallhackers) in older titles that I have spectated and that were obviously cheating and still ended with an average K/D of 2 or 3. And I myself have rounds where I have a K/D of 10 (not many, but sometimes it happens) and I am not cheating (not even with the official Paik cheats).