You look at the descriptions of Whitey by law enforcement during his early years, and they sum him up pretty well. He was the same guy 40 years later; he just had $40 million more, and had committed 40 more murders.
Lots of middle class people are running around pretending to be Cockney.
What has always surprised me when I walk into a bookstore is the number of books that you can find that are written with certainty. The authors tell some story as though it's true, but they don't have any evidence that it is true!