Originally Posted by NicktheGeek
You could do that in theory, but if they will need to sign up to login, then you might as well make them WP subscribers or make some other custom user role. Much easier than making your own custom user system.
Ok, thanks for the answer. As long as it can be done. These will be assigned roles to a limited number of people - business partners of various descriptions - and I definitely don't want to make them WP subscribers even if it is easier.