Dynamic Queue's MMR system has always existed. It was called Normals.

Did you know the Normals game mode has an MMR rating? Yes it does in fact exist as a hidden rating based on your performance in normal games. This is the game mode where you can queue by yourself, queue with 1 friend, 2 friends, 3 friends or 4 friends and you can play against any combination of solo players to premades who are also roughly in your same Normals MMR range. You can try as hard as you want to eventually get paired with higher Normals MMR players or play it with a more relaxed approach. You can play alone or you can play with your friends trying to carry them and the end results are consistent when you win or lose. Your Normals MMR rating goes up or down. Doesn't matter who you're with or who you're against. It's not uncommon for a game to look like this http://i.imgur.com/YZZsc8r.png Believe it or not, the individual players on these teams are within reasonable MMR ranges of each other which is why matchmaking allowed this game to go through. The only reason people would have room to gripe about this matchup is that we see a SOLO QUEUE rank indicating a massive skill disparity between the players when they tried hard in the competitive game mode known as RANKED SOLO QUEUE. A game mode where your rank is largely a product of your own individual effort and the one duo partner you could get couldn't simply carry you to a rank that was substantially higher than your actual skill level without being an extremely better player himself which was exceedingly rare. This made Ranked Solo Queue reliable to a large degree for determining individual skill. But that won't exist in season 6. All you will have is one game mode where can queue by yourself or with any number of friends and you will be matched against any combination of solo players to premades who have a similar performance in this queue and you get slapped with one MMR rating that indicates your performance but remains hidden. And another game mode where you can queue by yourself or with any number of friends and you will be matched against any combination of solo players to premades who have a similar performance in this queue and you get slapped with one MMR rating that indicates your performance in this queue but remains visible. The only difference between your ranking in Dynamic queue and Normals queue will be that one will be hidden and one will be visible, and neither of them will indicate your actual skill level in the game because they are literally structured the exact same way.