This time, an update brings a new MMR system that functionally gives players separate MMRs for each of the five roles included in ranked roles. Winning or losing games will modify your single rank. Though the return to a single MMR score might suggest that Valve is returning to the previous setup, this new system further segments things in ranked matchmaking. It should theoretically result in greater parity between teams, regardless of what role a player is assigned during the game. Previously, the MMR system only distinguished between support and core, with core encompassing carry, mid, and offlane roles.
Matchmaking Update 3/17/ | Matchmaking Feedback & Discussion | Forums | Halo - Official Site
We understand that some players, especially at the high end, have experienced a significant drop in matchmaking quality as a result of our recent iterations. We are committed to making matchmaking as good as it can be. For any party that includes an Immortal player, every player in that party will be considered the same rank as the highest player in that party. We think this trade-off is worthwhile at this high level, however, because matches are unlikely to be of high quality anyways with extremely disparate skill levels within a party given the shallow pool available.
The new Ranked season is here. The changes in this update will be rolled out gradually over the next two days as we iron out bugs. The calibration part of the new season will begin this Thursday. One big observation that we had since the previous update was that matches with misaligned roles had a meaningful impact on game quality. An example of this is when the mid player for one team has the highest rank on their team, and the mid player on the other team has the lowest rank.