I think Khan has more of a chance than most believe. He can be knocked out as has been thoroughly demonstrated before, however he is also extremely fast and can outbox most other fighters.
If he implements the right game plan, resists entering a slugfest and performs to his ability I think he can win the fight.
Brooks promotion and opponent choices are embarrassing. The guy has talent but you can't judge him accurately based on the tripe he faces. Get him in some decent fights before we can say how good he is.