Hey Miley, that ain't twerking!

“I know it when I see it!”

That’s how Supreme Court Associate Justice Potter Stewart replied when asked to define hardcore pornography, acknowledging that it’s difficult to describe.

Well, that’s how I felt when I watched Miley Cyrus performing her dirty dance at the wild MTV Video Music Awards performance of Sunday night.

And I didn’t see it. Not at all! And I looked over and over.

Contrary to every major news report in American, Cyrus did not “twerk.” She didn’t even come close to it.

What she did do was bend over and grind and shake. But the TwerkScale® registered a zero – a failing grade.

Why is that? Well, to make that call, one has to know what twerking is … and what it isn’t.

Denise Clay is a freelance writer and political columnist who first exposed me to the term in a Facebook posting she made earlier this year. When I contacted her for this interview, Clay messaged me, “How did I know that's what you wanted to talk to me about?”

Guilty. I’ve run for political office. And I guess you don’t qualify to get on the ballot – as a male – anywhere in this county unless you have some kind of dark or perverted past – hopefully not as salacious as Anthony Weiner’s or Eliot Spitzer’s or, in Philadelphia’s case, Willie Singletary. But you certainly can’t be a Mother Teresa and expect to be elected in Philadelphia.

So considering myself an expert on “twerking” but not willing to share my point of view for fear of influencing her response, I posed to question to Clay: What is twerking?

“Twerking, or at least my understanding of it, is a dance that involves moving the hips in such a way that the derrière bounces,” Clay messaged me, adding, “It is sometimes also called ‘booty popping.’ There are folks who consider it an art form and one group, the Twerk Team, is best known for it and has made millions from music videos and club appearances.”

I then asked Clay whether Cyrus actually twerked.

“As for Ms. Cyrus and her ‘Adventures in Twerkland,’ she's apparently been twerking around the Internet all summer. While the moves she made appropriate twerking, and in a purist sense that's what she was doing, most of the people I know who are true students of twerking say that you need a voluptuous, or any, ass to Twerk. On that scale, Ms. Cyrus fails,” Clay concluded.

Okay, that’s a journalist’s take. How about a real live stripper’s opinion?

This is “Penelope’s” second time gracing U-Turn. The last time around she commented on the couch dance tax. Penelope is a former adult entertainer who once danced at Philly’s own Cheerleaders.

Miss Penelope’s take? “First off, a young lady at the club I worked at taught me how to fire the muscles on my backside to 'twerk'. It's hard. It really is,”Penelope told me, adding, “I hope that 'twerking' doesn't become a catch all term for butt shaking, because Cyrus did not 'twerk it'.”

Penelope continued: “Almost everyone I know who knows how to twerk (3 or 4 people) were taught by someone else. It's almost like a talent that has to be passed down to a deserving soul. And when you're taught how to do it, it's so counter intuitive ... it's not the muscle you think you should flex to get your butt to do that.”

I asked Penelope to be a little more specific.

“It's the same principle if you look at a hula dancer,” Penelope said. “They flex and fire muscles on the left side of the body to get the right side to move. I think it's wonderful and it's so mesmerizing to watch. Oh my god, is twerking urban hula dancing?? LOL!!”

Well, this made me wonder: Can anyone actually teach urban hula dancing? And for the ladies who want to learn, is there any place local that teaches it?

“Twerking isn't for everyone -- especially Miley! It's takes a lot of coordination to get everything to flow right when you’re moving your hips and butt up and down simultaneously,” said Lauren "Pinki" Schiavo, the owner of Flaunt Fitness in South Philly, who was more than happy to say, “If you would like to learn how to twerk from the professionals, contact us! We will teach you the right way to do it!”

I never thought I’d see “professionals” and “twerking” in the same sentence, but we’ve come a long way, baby, I suppose.

“Pinki” made me an offer I can’t refuse. After our interview, she told me, “I have designed a class specifically for this -- Squats in Stilettos! I would invite you to join us anytime you want -- on the house!”

If I don’t say this enough, I love writing for Philly.com.