"Kate is pretty dreadful," he said matter-of-factly on "Lopez Tonight" Wednesday. "She's entertaining…People like disaster movies -- I'll tell you, we have our own disaster movie there every night.'2012' is nothing compared to the catastrophe she produces."
Though he criticized her dancing skills, he did give the reality TV mom credit for trying hard.
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Past "Dancing" Champions and Competitors
"She's a tough cookie," he continued. "She comes back, she tries to get better…it doesn't really work."
Tonioli also talked about "Dancing with the Stars" beating "American Idol" in the ratings, how the judges have to be impartial and showed off footage from his dancing days.
Watch the video below to see the entire interview: