Not only could the queues become more stratified, but how does the algorithm ‘round up?’ Who becomes the mathematical lowest-common-denominator* and an easy scapegoat for the group to point to if things progress sub par?
The difficulty is this system assumes there is a score to begin with. But if this system went live when the patch/season started, there would be plenty of 0 iO’s What if a season 1 800iO dps is paired with a season 1 1800iO healer? Would the 1800iO tank risk slowly increasing their iO with this system?
Additionally, we have this thread as evidence to suggest that if a two-player group was entering the M+ queue, and such a disparity existed that caused frustration for the other players, it wouldn’t be as fun. Imagine if, in that 2-person party, the party leader had 0 iO, but the tank they were queueing with - a friend - had 1400 iO. They get a +2 dungeon. The 1400 iO tank can solo the instance, and pulls very dramatically and causes the healer great stress. In this example, we’re back to an issue where there is a misalignment of expectations and skill, all perpetuated by an automated system.
Who is in the wrong here in this scenario?
There are a lot of potential unintentional consequences here.