How do you calculate the odds of winning between a random team (or with a duo queue) against a full premade (or with a double duo or duo-trio queue)? If you are averaging, then two low MMR team mates will pull the overall MMR of the team, making the full premade team face against a random team of lower MMR (thus they have some advantage). So two players will make f2p accounts and boost the other three, and then the three will do the same for the other two.
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