I hated Eszterhas's films as a kid, but as I went to the movies almost every week (sometimes twice or three time) I couldn't avoid them. I remember being extremely disappointed in Jade, after hearing great reviews. When I realised all the films I most despised (Jade, Showgirls, Sliver) were by the same writer, I expected to detest his book.
But, this is not like one of those plotless movies. In fact, it explains some of the changes from his original scripts. And, after reading this, I saw his much better work "The Music Box."
Eszterhas was typecast. Like many screenwriters, he didn't win a contest, he didn't even want to write screenplays, but was recruited after being a successful journalist and novelist.
There are some graphic parts of this book, but it is paced so you can pretty easily skip over them. The main lesson for filmmakers is that 1) many producers don't ever read a script. 2) a great script can be destroyed. 3) everyone wants to be a screenwriter 4) producers, directors, crew etc usually don't know how to write screenplays. But that doesn't stop them trying to muck with scripts.
He indirectly admits to many writing mistakes too.