Any form of dance experience, whether it’s the likes of Debbie McGee’s professional ballet career, Caroline Flack’s dance/musical theatre background, or Denise van Outen ‘sitting on a chair’ in Chicago, is barely ever mentioned on the show, so I cannot imagine vast swathes of the audience feeling ‘lied to’ if they find out that an actor did ballet as a kid but it was never formally declared on the show.
Angela S had professional Irish dancing training, Les has been touring in 42nd Street, most actors/performers have had dance lessons at some point. Even pretty much every woman (and a few men) I know has done some sort of dance class at some point. Finding 15 celebrities each year who have never had so much as a single dance lesson at any point in their lives is a Herculean task.
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They should swap places one week and see if anyone notices
(Though if they do, it’d probably have to be next week as I’m not sure there’ll be many more weeks that they’re both still in the show).