Actually, this is one of the times that Weingardner got it right. Most of his references to the story came from the novel, and its in the novel that Vito killed Fanucci before Mike was born (its explained that Vito sent his wife and two children - Santino and Fredo - down to the street as he prepared for his hit on Fanucci).
Weingardner chose to disregard many of the more accurate events from the movie and chose to get his background only from the novel. One glaring error from the novel, and somewhat related to Fanucci's killing is Sonny's admission (to Vito) that he witnessed the killing. This was in 1933, when Sonny should have been 23 years old, but the book explains that he was only 16. (The book's beginning described the 35 year old Santino at his sister's wedding in 1945. We, therefore know that Santino was born in 1910 - according to the novel).
Regardless of this mistake by Puzo, Weingardner knows more about "The Godfather" than anyone else alive. If you don't believe me just ask him. (He stated that in a press release before his book went on sale). :rolleyes:
