The Swans captain was blasted by the United boss after December's 1-1 draw at the Liberty.
A Williams clearance hit Robin van Persie in the head after play had been stopped and Scot Fergie raged he had risked killing the striker.
He said: "I think they have got more to think about and celebrate than that.
"I laughed about his comments at the time. Most people thought it was ridiculous.
"But he is the top dog, a top man and the Godfather of the British game.
"It would have been good to play under him and see how he motivated players."