The 500th episode of 'Dancing with the Stars' taught plenty

Inserting an “instant” dance (which gave contestants mere minutes to concoct a number) was a brilliant move. It let the celebs show how much they’ve learned and how far they’ve managed to come.

But what else have we learned?

1. Getting rid of posers early on is a good thing. When it gets down to real competitors, the show pops. Letting celebrities walk around a smoke-filled floor merely makes the show drag.

2. Carrie Ann Inaba wants to be the “tough” judge. She offers criticism to elicit a response and often has to quell the crowd when they boo. She’s better when she's encouraging. Her “lift” rule, by the way, has fallen by the wayside.

3. Athletes are good contestants. They’re used to performing in front of a crowd and, in this arena, they bring it. Danny Amendola, for example, knows  what it takes to get the fans on his side.

4. Leaning into your shortcomings can be advantageous. Dwight Howard, who must be three feet taller than his pro, has consistently overcome the problem. On Tuesday’s show, he and Daniella used a platform to do an Argentine tango and it worked. When size became a problem, he used his muscles and hoisted her like an NBA trophy.

5. Personality sells. Ilona Maher, the Olympic rugby star, oozes personality and wins over the audience. Ditto: Stephen Nedoroscik, the bronze medal-winning gymnast.

6. Saluting the past works. In addition to filling the ballroom with past contestants, the producers brought back memorable dances from previous winners. Great idea.

7. Sex always sells. Amendola cracked his shirt for the instant dance; Joey Graziadei used moves he should have considered as “The Bachelor.”

Because there are good dancers still in the competition this is an “it’s OK no matter who wins” year. And that’s what the producers should remember. Putting in politicians, fading stars and scandal-prone celebs isn’t a good idea. Go for people who can move, not make headlines.

While Chandler Kinney got two perfect scores (setting herself up as the one to beat), it’s still close. Graziadei and Nedoroscik are too close to discount.

Leaving this week: Dwight Howard and Daniella Karagach. 

Luckily, we’ll get to see them on the finale as performers.

Maybe on the 1,000 show someone will do a salute to them and the strides they were able to make.