You need to ask him for that. But about flat management - I heard many people saying flat management system have turned Valve to the highschool-style community

You need to ask him for that. But about flat management - I heard many people saying flat management system have turned Valve to the highschool-style community with "Cool Kids" running things and some people being pushed into the "corner". I have read stories where people comment on how a lot of things are immature in the company. Sorry, I am busy coding now so cannot send citations your way, but they are not hard to find with Google.