Balancing games because of premades is unhealthy
There are similarities and discrepancies in each ranking, but let's assume that each tier has has its own identity. For example, higher tiers know how to close out a game when they are ahead better than lower tiers thus making comebacks in lower tiers more prominent. Riot wanting to make a match as close to 50/50 as they can is a positive notion but not when it involves a large relaxation in mmr. The bigger the gap in mmr, the more variables which makes it harder to properly assess a fair match.
In the Round Table Video, Lobster stated clearly that premades have a higher chance of winning (when looking at similar mmrs) - duh!? So what does Riot do: they say, "Alright, since Team A (premade) has the advantage let's give Team B (solos) some higher mmr players". In my own experience I have seen this gap be as large as a Diamond 5 on my team compensating for the Gold 3 on their team who was in a premade. In that same game the largest gap on our team was a Diamond 5 to a plat 5.
This destroys the intent of the game. Throwing all of this mismatched mmr into a game makes things messy. The Diamond player is not used to playing with lower mmr players and may expect them to do things that they don't do. The gold 3 could be pitted against the Diamond player and cost Team A the win. These are the variables I am talking about. The matchmaking system doesn't take into account who is going against who in lane, and big mmr differences are unfair. Something beyond the players control that takes place before the match even begins has a huge potential to decide the outcome of the game.
Furthermore, there are different kinds of premades ranging from casual to competitive and the matchmaking system is unaware of this and strictly looks at **SOLO MMR! ** People are playing as premades but being assessed off of their individual skill, not how well their premade performs. The system says you can play with friends and encourages you to do so, but it only looks at individual performance despite the inherent stress on premade play. The system is messy, unhealthy, and sending mixed messages to the players. Please fix it for next season Riot.