CN coins need a hard fork to change the algo or the CN algo will gonna die for gpu mining.
I agree that bitmain wants to compromize the main feature of crypto currencies by centralizing the power.
Not sure if they are doing it intentionally, but given their position; I think its a matter of inevitability. When you come up with an invention, you'd be stupid to not use it yourself. I'd say much of Bitmain's
profit comes from mining and not actually selling their rigs. But that's a hypothesis. Otherwise, they'd end up like KNC or Butterfly Labs.