Need help finding where Riot talks about dynamic queue vs the old system

I remember reading a Rioter talking about problems with the old system, how 5's matchmaking was shit and it was hard to get 5 people together. I want to quote that and respond to it, but can't find it. Anyone have the link?

I might have been a blog post, or comments on one, or dev corner, or red tracker, or maybe ghostcrawler's ask.fm...

If I don't have the answer yet, I'd appreciate upvotes so more people see this. Once I get the answer, please downvote because then it's just clogging up Boards.