Consistency or suggestion to rename article 

Most of the article refers to "Parker", yet the title remains Butch Cassidy.  If we recognize the appropriate name for the article as Butch Cassidy (and Robert LeRoy Parker as a redirect), then it makes sense to keep some consistency and replace the "Parker"s with "Cassidy"s.

On the other hand, if it's best for the article to refer to him as Parker (as it does), then I suggest renaming the article to Robert LeRoy Parker (with Butch Cassidy as a redirect).