In reply to Otto.

No... I'm talking about the method we add notices in WP.

Let's say you add a notice to the Manage Themes admin page: http://codepad.org/BQZ4UpO0

If you close the notice, but revisit the Manage Themes page, the notice will appear again. There should be an easy way for developers to make it dismissable forever. E.g.: div class="notice notice-success is-dismissible" data-dismiss-duration="forever"