Re: An awful lot of books - or their content - are copyright
So, if I send a message that there is a juicy picture of page 125 of a slightly obscure book, and maybe where that book may be found, am I infringing copyright?
No, firstly because a physical book was presumably published with consent and someone paid for it.
OK, let's say where an unauthorized reprint of that book may be found. It's not obviously violating copyright - it's not a crude photocopy. The copyright owner contacts the person with this illegal book, he shreds it, and you are informed by the copyright owner that it wasn't a permitted copy and how to tell the difference in future. You then alter the document you published to tell people where to find another unauthorized copy, this time in the full knowledge that it is unauthorized. And repeat. And repeat.
I think that's a fair analogy to this case.