They just always ruin games. I just had a ranked game whereby they got jungle and support so forced the adc to go jungle so that they could be together. The adc had no clue how to jungle and ended up massively feeding lanes as he would do horrific ganks.
It's really just the worst thing. Then you have the whole business of a 4 man premade which, from my experience, always loses.
Can't riot just bring back teambuilder for premade teams. They can then have fun and we can just play without them forcing all the decisions upon us.