Williams would school Froch even worse then Dirrell schooled Froch
But Dirrell and Williams fight nothing alike. Williams would not be effective at 168, wouldn't be enough power to keep Froch off him, he's not a skilled boxer, in the classic sense, that is to say he doesn't box or use his height advantage and likes to fight on the inside, and Froch has a lot of power and Williams chin has not been tested really at 168.
So IMO, Froch would probably KO Williams within the first 5 rounds. Unless Williams showed he could take power up and his chin. But as of now, there's no proof of that.
Williams would school Froch even worse then Dirrell schooled Froch
Worst post ever....Williams takes a lot more punches than Dirrell and would get knocked silly by Froch, who has a much bigger frame and is much stronger.
The main tool Williams has is workrate, and Froch will walk through those pitty pats and club him to death, caveman style.