Derek Hough and Mark Ballas' Twitter Tirades Against 'Dance Moms' Abby Miller

"Dancing With the Stars"' cast members Derek Hough and Mark Ballas have taken to Twitter to express disapproval of "Dance Moms" instructor Abby Lee Miller's tough approach to teaching.

Hough tweeted on Wednesday, "I'm sorry, but this 'Dance Mom' show is straight up abusive. … Kids Run!!!!!!! It ain't right. Child abuse isn't right. I'm livid right now. … I believe in discipline and a strong work ethic. But there is nothing productive about screaming and making little girls cry over being on the wrong foot."

Hough's castmate Mark Ballas also joined in on the Twitter disapproval: "This teacher lady is crazy… completely wrong attitude toward  the kids. It's embarrassing," he said.

In its second season,"Dance Moms" showcases Pittsburgh's Abby Lee Dance Company and the 6- to 13-year old children who take classes there.  The girls and their mothers are kept in check by the owner and dance coach  Miller.

Monday on "The View," Miller defended her approach, saying, "Some kids you have to yell at. Some kids you have to take a baseball bat - which is foam rubber, by the way - and straighten that knee."

But not  all stars have taken the bat to Miller's tough teaching.  "The View" co-host Whoopi Goldberg compared Miller to Mary Lou Retton's Olympic coach, Bela Karolyi.

Experts tend to take the side of Hough, though, emphasizing that parents need to decide for themselves whether  their child is in an abusive environment, or merely a strict one.