Global Site Navigation: Not Worthwhile?
http://www.uie.com/brainsparks/2005/10/19/global-navigation-not-worthwhile/

Spool, Jared M.
GUUUI
2004

Abstract:

Having global navigation isn't a bad thing. It's just not something that should garner a lot of resources, as it's unlikely to be important in the user experience. You're probably better off putting your resources elsewhere (such as increasing scent for the most important content on your site).