So there's apparently a controversy over whether Natalie Portman did or did not do her own dancing in "The Black Swan," a role for which she won the Academy Award. The ballerina who doubled for her, Sarah Lane, says that maybe 5% of the dancing was Portman, while the choreographer, who also happens to be Portman's fiance & baby daddy, says that he choreographed mostly easier moves that she could do, and only the technically tricky shots & footwork were doubled. The debate: does it really matter?
I haven't seen this movie so I'm flying blind, but I think a good movie is going to be about the story & the believability of the characters. You need to believe that Portman's character really is a ballerina, but you don't really need to believe that Portman was the one dancing. If the story isn't enough, great dancing isn't going to make up for it. She got the Oscar because she had a good story & made her character believable, not because people thought she did the dancing.