Why Do People Follow Bad Directions?

Nicholas Forbes writes with an interesting question about why people follow bad directions — covered here ad nauseaum — that is above my pay grade:

I am a Ph.D. student at the University of Nottingham UK. I have been running research recently into the phenomenon in which drivers receieve inaccurate instructions and follow them.
Specifically from a psychological percpective, I’m interested in whether this is caused by deficient attention (to surrounding road signs and environmental information) or excessive trust in the navigation system or both.
I’m trying to categorise and classify mapping errors that drivers receive most frequently from navigation systems. I have been searching the web (with little luck) to find online sites or forums in which people have reported errors they have received. Unfortuntely the Navteq feedback site doesn’t divulge any feedback they have receievd.
I was hoping with your experience in this area you may be able to point me in the direction for any online resources of this kind of information, particularly any resources that list mapping/routing errors drivers have received.

Previously: Case in Point: Driver Obeys Directions, Gets Car Hit by Train; Apparently I’m a Pundit Now; Plunging into a River — That Makes Sense; ‘Do Not Follow Satnav’; Ambulance Goes Slightly Astray; More German Driving Misadventures; Hang a Left at the Pile of Sand; Getting Stuck in a Narrow Welsh Laneway; Because My Car Said So; Crackpot Directions Send Drivers Along a Cliff.

Update, 6/17: Nick has a study page (via Fabien Girardin).