The former Everton and Burnley boss remains unconvinced by the Portuguese and his methods.
"I may get hammered for it, but I bet I could win more games with that squad playing a 4-4-2," Dyche told ex-England manager Sam Allardyce on the No Tippy Tappy Football podcast. "People keep talking about his philosophy and it isn't working. It's fine getting to five or 10 games, but once you get to 20 games, it clearly isn't working.
"I might be wrong because they've brought in three big hitters this summer, so it wouldn't work with the players they had, but maybe the new players will do better.
"On the one hand, I like the fact they're sticking with it, and it is Man United. You're under massive pressure to get it right. But on the other hand, you wouldn't normally survive that situation. Amorim's been given more time than most.
"People forget that in Pep's first season, he made so many changes to the squad and played so many formations and finished 13 points off the top, nobody blinked. If he was at Real Madrid, he would have been sacked. But he learned and won the Premier League the next season."