When you're not logged in you have no easy way of knowing if you see all posts of a pool in its overview.
-> When a pool contains posts hidden by the global blacklist the pool page just doesn't show them at all, not even blanks, placeholders or a warning that not all pool members are listed.

Here's an example:
https://e621.net/pools/8574
https://e621.net/posts?tags=pool%3A8574
The pool is 14 posts short when not logged in but the posts-search has a clear warning.

@admins and whatnot: Please let pool pages inform not logged in users about missing pool members. Thank you.