Someone named Marianya who auditioned for So You Think You Can Dance in Chicago takes us behind the scenes of the process:
Contrary to what they showed on TV, nobody got a free pass to Vegas after their solos. The judges determined who they wanted to see more of, and all of those people were sent to the choreography round. After they chose who would go to Vegas, they cut the footage of the best dancers to make it seem like they went straight through.
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