It is commonplace for authors to say something kind about those who helped them compose their book while saying something like, “Any remaining shortcomings are solely my responsibility.” This evening I was reading Friedrich Nietzsche’s Prologue to his On the Genealogy of Morals when I read this line that both made me chuckle and reminded me of what a jerk Nietzsche was:
If this text strikes anyone as unintelligible and far from easy listening, the blame, as I see it, does not necessarily rest with me. The text is clear enough, assuming in the first place, as I do, that one has put some effort into reading my earlier writings: for these do, in fact, present difficulties. 
So, there you have it! If I don’t understand the book I’m the idiot. Good to know!
 Nietzsche, Friedrich; Douglas Smith (1997-01-23). On the Genealogy of Morals: A Polemic. By way of clarification and supplement to my last book Beyond Good and Evil (Oxford World’s Classics) (p. 9). Oxford University Press. Kindle Edition.