Can a user receive notifications if they haven't been assigned to a group?

[Trevor Hunt]

I read somewhere that you should be able to do this, but when I've added watchers not in the users group, notifications don't appear to be going out to them.

The users exist in the directory, they've just not been assigned to any group.

I don't want them to have access to JIRA, but I do want them to receive notifications when an issue's state changes, etc.

[codelab expert]

The user should have the permission to login and to view the project.