Fernando R. Tesón (Florida State University College of Law) has posted Fake Custom (Brian Lepard (ed.) Customary Law, Cambridge University Press, 2015, Forthcoming) on SSRN. Here is the abstract:
Lawyers often make international law arguments that lack support in practice but they still call "custom."This rhetorical device, fake custom, is designed to exploit the high informational costs that the audience has to weed out real law from pure advocacy. The article analyzes the various techniques utilized by perpetrators of fake custom.