I read on http://en.wikipedia.org/wiki/Academic_publishing :
One of the earliest research journals is the Philosophical Transactions of the Royal Society, created in the 17th century. At that time, the act of publishing academic inquiry was controversial, and widely ridiculed. It was not at all unusual for a new discovery to be announced as an anagram, reserving priority for the discoverer, but indecipherable for anyone not in on the secret: both Isaac Newton and Leibniz used this approach. However, this method did not work well. Robert K. Merton, a sociologist, found that 92% of cases of simultaneous discovery in the 17th century ended in dispute. The number of disputes dropped to 72% in the 18th century, 59% by the latter half of the 19th century, and 33% by the first half of the 20th century. The decline in contested claims for priority in research discoveries can be credited to the increasing acceptance of the publication of papers in modern academic journals, with estimates suggesting that around 50 million journal articles (see Reference 1) have been published since the first appearance of the Philosophical Transactions.
Reference 1: Jinha, A. E. (2010). "Article 50 million: An estimate of the number of scholarly articles in existence". Learned Publishing 23 (3): 258–263. doi:10.1087/20100308. Archived from the original on 2012-05-23
How comes 92% of cases of simultaneous discovery in the 17th century ended in dispute, whereas authors had often "encrypted" their results to be able to claim paternity later on?