Why should mmr dictate rank or flipping it around why should ranks stick around when mmr decides it?
I've heard the story of riot changing from the mmr system to the "rank" system (while still keeping mmr in the background) to appease people who fluctuated a lot but I really don't agree with the system currently in place.
My first season I was silver 1 playing against high gold and low plat every game because I took the time to learn the game before starting ranked. I got to gold promos 3 times in a 2 week period (during which I was still going to college, mind you) because I had the mmr to make it happen.
Despite this people will look back and say "look at this guy who got stuck in silver." Is the system really doing its job when it holds players like me down rather than providing that "failsafe"?