Look what I've found:
One of the two professional costumiers that supplies dresses to Strictly is DanceSport International in Croydon. DSI hires the dresses to the BBC, and then sells them to anyone who could possibly want a half-dress made of fringing and feathers in some eye-burningly luminous shade. Twenty-five dresses worn on Strictly are being shown on the DSI website as I write, prices on application. Every dress is based on a leotard; some of the celebs choose to wear something under the leotard, others don't. Even the virtual nudity that features in so many of the Latin routines is fake, although the grotesque bump and grind is real enough.
I know. Anyone would have thought I had written that, but it was in fact Germaine Greer.
Read the rest of her article in which she whole heartedly agrees with moi here.
Great minds think alike.