Add a permission to the block/ to limit who can see this.
You could use Entity Path to redirect the bean entity view url's elsewhere, access denied if you like.
There was a small typo, here's a patch.
Automatically closed -- issue fixed for 2 weeks with no activity.
Actually, the <delta> is never displayed, I believe Drupal strips it off thinking of it as an unknown tag :P
Changed it to 'description' => t('Visit !url', array('!url' => 'block/< delta >')),
'description' => t('Visit !url', array('!url' => 'block/< delta >')),
Not perfect but it works.
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