I seriously doubt that skill is the main factor for gaining decent mmr in Blitz.
TWW S1 I played on my lock and got 14 losses in a row. Remained at 1500. It felt like there was absolutely nothing one could possible do to sway a win. So I gave up Blitz. This season I tested again, with much better results. One lock is now 2400+ with almost 65% win ratio, the other 2200 so far. But, my MM hunter is 1400 with 33% win ratio.. I mean damn, i get streaks of loss so huge, the biggest was 17 games lost in a row.
I play on my MM hunt just as well as on wl. all my chars are 2.3 mmr shuffle. I bring best dps and contribute to objectives as much as on other characters, but on MM my team is always clueless, like bots. The only sense i can make is that the system is seriously flawed, and puts players with low win ratios in to the same team or something, and once you get too much below 50%, there is virtually no way out of that hole for entire season.
Dont know what else to say. It just feels very strange to me and I cant explain it any other way.