It's not flawed reasoning at all. If you are great with both, you will choose the DMR based on your criteria. Some people will even choose the AR based on their style of play. I played in a game with Bravo last week and we dominated the other team, I finished second, I used the BR, he used DMR. If I had used the DMR, I'd have finished lower. The math is indisputable, but style is about personal preference and ranges of ability. I'm not, but you can imagine for example that I might be better at jumping or dodging than Bravo. Looking at a single number ignores the millions of other variables involved. think you'll see MLG etc settle very quickly on one weapon, but you won't see that as a universal in matchmaking, I don't think.