Reminds me of how Orwell preferred to write introductions to 1984 only for illegal reprints behind the iron curtain. I can't find the exact quote but he said that he'd write it for that audience alone as he knew without a doubt that they would read his introduction. If I ever actually write a book, I hope I have enough courage to do the same and only write introductions for cracked copies. You know the audience actually cares if they are willing to risk the fuzz just to read.