Installing an Unsigned Driver During Development and Test (Windows Vista)
http://msdn2.microsoft.com/en-us/library/aa906338.aspx
This one even includes a registry modification to allow unsigned drivers
to
load on a permanent basis.
Registry settings mentioned in article you are referring to control how
unsigned drivers are handled WHEN kernel debugger is attached to the system.
Attaching debugger automatically disables driver signing enforcement so if
developer wants to use debugger AND check for problems associated with the
fact that drivers are not signed at the same time, s/he can use these
registry settings to control driver signing checks. However they have
nothing to do with allowing unsigned drivers to load on permanent basis.