This article is in unfortunately in german:
http://www.spiegel.de/spiegel/a-709761.html
But it is about an historian, who believes that much of the german success in the 19th century results from the fact, that there was no copyright in germany. Books where cheap and plenty. For reference: in england around 1000 books were published per year, in germany 14000. Much of this was "self-published" and of practical nature. Authors had to be fast in producing books, as they were copied and had a only a short phase of exclusivity.
I am not sure, how much of this effect is because of no copyright or if the low prices would be sufficient. So maybe it is more similar to the current self-publishing and the spread of information through the internet. But it shows, that there needs to be a balance.
By the way did the usa something very similar. Works with american copyrights were protected, but books from other countries weren't.