Dynamic Queue will never have balanced matchmaking
Rio recently released a new matchmaking update that pointed out how they have improved matchmaking for teams of 5 vs teams consisting of premades of 1-3. The statisctics show that Riot has increased balance to near 50/50 winrates for these teams.
The statistics lie.
Teams of 5 have differing capabilities. Some will have voice comms, some will not. As long as these two groups even out, Riot can and will manipulate the statistics as much as they want.
A group without voice comms will be matched against players with vastly greater individual skill and will subsequently be slaughtered trying to best players better than them on even footing.
A group with voice comms will use their superior macro play and synchronicity to overcome these challenges and defeat the opponents with ease.
As Riot cannot and will never be able of knowing which scenario is true, there is no way for both to be balanced.
Ex: 70% of 5 player teams use voice chat, 30% don't. If the 70% won 60% of their games and the 30% only won 35% of their games, then you would get a 52.5% winrate for teams of 5 vs non teams of 1-3. Whilst 30% of those have an atrocious chance of winning.
Not to mention that teams of 5 without voice chat vs teams of 5 with voice chat is essentially pitting 5 randoms against a team without the MMR differences that make the near 50% winrate Riot has fabricated.
Riot cannot balance for this and there is no way for them to find this information.
RIOT CANNOT BALANCE FOR THIS AND THERE IS NO WAY FOR THEM TO FIND THIS INFORMATION