I agree with your principle there. The knowledge to detect fakes is a valuable commodity. But if I as a collector should invest in a book, why wouldn't a conman who is investing thousands in materials, tools and dies, also not buy a book? That said I am frequently amazed at how a faker can spend so much time on a fake dagger, but miss something so obvious such as wrong screw positioning.

By the way, I have invested a considerable amount of time and money building up a reference library on the subject, and always advise burgeoning collectors to do the same.