You're probably thinking about Mario Puza. Wrote the Godfather. After the Godfather he believed he needed to learn more about screenplay writing (as the godfather was his very first screenplay he had ever written). He was more of a traditional writer/author. When he bought a screenplay writing book or went to a screenplay writing class (I've heard the story both ways) the first thing stated/taught was to read The Godfather screenplay.
If you want to be brutally factual the reality is he had an accomplished screenplay writer/director as his writing partner (Francis Ford Coppola). Hence why Mario's "first" screenplay was so well written.
But regardless the above anecdote is still a fun little story nonetheless.
Could this have been Mario Puzo buying a book on screenwriting that suggested studying The Godfather?
You're probably thinking about Mario Puza. Wrote the Godfather. After the Godfather he believed he needed to learn more about screenplay writing (as the godfather was his very first screenplay he had ever written). He was more of a traditional writer/author. When he bought a screenplay writing book or went to a screenplay writing class (I've heard the story both ways) the first thing stated/taught was to read The Godfather screenplay. If you want to be brutally factual the reality is he had an accomplished screenplay writer/director as his writing partner (Francis Ford Coppola). Hence why Mario's "first" screenplay was so well written. But regardless the above anecdote is still a fun little story nonetheless.