If you have an interest in something and you work your butt off to prove yourself, we try to give you more and more of the work you want. As long as you don't screw up, we keep on going.
@GentlemanSquirl initially gave me lots of very high level/pro player feedback on balance, meta game, etc. all during Evolve development and especially after launch. Then he started to paying a lot of attention to the new player experience and giving feedback on that.
After a bunch of DLC's, I needed to move onto a different project so we posted a job for a lead designer who could help with Evolve. Brandon said he wanted the job. I was really comfortable working with him. We had already developed a lot of trust so we decided to try it out for a while.
Two months later I was hardly involved in Evolve at all and that is something that is really valuable to me. The less I need to worry about, the better. I have plenty on my plate already. Brandon comes and talks to me when he wants to. Gives me updates, asks what I think about particular things. I go to him when I have an idea or when I don't like how something feels in the playtests. It's been working out well so as long as he wants to keep doing it, he gets to.
He also built the balance team, pulling pro players from the community to play the hell out of the game and make tuning adjustments along with studying the telemetry. These guys all work together to do a much better job than I could do alone.