After viewing a thread, you typically have to use the arrow key to go back up to the top to navigate. It is possible to put your navigation symbols at the bottom of the page for easier navigation.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .