How Super User (and probably all Stack Exchange sites) handle clicks to preview areas for posts currently being written is confusing and horribly inconsistent:

• If I click the preview pane for a new answer...

  The page focuses on the associated answer text area, i.e. the input field that is used as source for the preview I just clicked.

  Very useful for longer posts, especially in topics with several answers, since it makes finding the text field trivially easy.

• If I click the preview pane for an existing post I'm editing inline...

  Nothing happens. The current text area loses focus.

• If I click the preview pane for a Q&A style answer written parallel to the question...

  The page focuses on the text area for the question?!

  Surely you jest! What's next, focusing the search box?