My dd did this 2 years ago. It really did change our vacation at all. She had her workshop on Thursday and they danced at Downtown Disney on Friday night.
Since the team was scattered and not staying at the same place, we met at the parking lot at Downtown Disney on Thursday morning, and the girls were bused to their workshop. We had to pick them up in Epcot when they were done.
My dd had fun at the workshop (she was 14).
Friday night, I had to bring her to the parking lot of Downtown Disney, again, I think they were bused some where. Their teachers were the only ones allowed to go with them. I can't really remember what they did. I took the boat to the stage and just walked around waiting for their performance.
It was a great experience for my dd.