All menu items have capability to access the pages. Also Adminimize – there use manage_options for the access check. You can change a role for his capabilities also via a plugin: Members. If you add this capability to a role, this role have also all other access to pages, there check for this, like Settings in the default. IF you hide also the Adminimize settings, then you have not the chance to access this page, right. But you can activate this option separately in the plugin settings ‘Allow Page Access’ and now the menu items are also hide, but if you know the link, the url, you can access them.