title: Change order of blocks via local.xml file
body: <p>Is it possible to change the order of already existing blocks via the local.xml file?
  I know you can change the order of a block with the after or before attribute, but how can one change those attributes of existing blocks.</p>
  
  <p>For example, if I want to place the layered navigation block underneath the newsletter subscription block in the left column, how would I do that?</p>