Since it resets at the beginning of every week, it seems like just a gatekeeping function from having to play multiple games in a row with the same problematic players. It doesn’t function as a tool keep you from ever having to play with someone ever again unless you have the energy to re-add someone every week.
Correct, for most of us plebs outside of very high MMR we will rarely really see the same player again on our team outside of happening to re-queue at the same time after a game. So we build the avoid list to maximize impact in this case (I can guarantee I won't see someone problematic in the near future, especially the next game) and the weekly reset reduces the possibility of edge cases causing serious matchmaking problems. The abuse possibilities and queue time impacts are unfortunately why we can't enable this at higher ranks.
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