I suspect Ion is a good manager of teams and producers. That's his main job, not drafting out every little detail. By all accounts he's good to work with and of all the managers that have been at Blizzard for years, he's one of a very few that came out of all of the recent uproar clean. He's not likely to go anywhere unless he's promoted up the line or takes over a new unannounced title.
Most of what he does if it's like any other management job is sit in meetings, works for design consensus, keeps everyone on schedule and on the same page.