@krileon: see screenshot below
After showing that "half" page it automatically redirect to the registration page and states that a registration and subscription is needed.
Some of the blog posts are categorized as "Blog (public)" (not protected by CBSUbs) and some are categorized as "Blog Community" (protected by CBSubs.
Normally, every uses can see the intro text of all blog posts. But as soon as JComment is enabled, CBSubs will prevent a user from displaying the intro text ...
Is it now better understandable for you?