Harris of USC and Davis of TAMU both ran 13.35 in their conference championships. For Harris, that is Pac-12 and facility record, and he outperformed his coach in Shanghai, who happens to be the defending WC silver medalist. I don't think either Harris or Davis will have any real competition until the NCAA finals, so it's conceivable that both could have won in Shanghai.
If Liu ran a 60 or 100 against somebody like Terrence Trammell, he would have been annihilated, and there's a limit to how far you can get on "practice, practice, practice" if the other guys like Robles and Merritt simply have more pure talent.
Now get this: At the Pac-12s today, Aaron Brown ran 20.26 into -2.1 and that converts into easily the fastest time in the world and possibly sub-19.8 with +2.0. And that comes after prelims of both 100 and 200 yesterday , and winning the 4X1 and 100m today. Also, the track at Washington State is not exactly the rival of Shanghai. The Canadians may have themselves a 200m medal threat for next year.