Riot's engineers suck at balancing MMR. Give us the option of opting out of premades.
I've played a lot of games. A lot of those games have been against premade teams. A lot of those premade teams have been either 1) more toxic than the average solo queue player or 2) a significantly lopsided victory/defeat.
Since your engineers can't figure out how to balance MMR why don't you actually give us "SOLO QUEUE" instead of pubstomping-queue?
I've played 3 games tonight and all three were either with or against the same 4 man premade. All three times the premade destroyed lanes. I've had other games where premades just flat up suck. While the mean score differential of all games with a premade might be the same as an all soloqueue game, I'm fairly certain any single premade game will be more erratic than the average soloqueue game.