title: Warning: Unexpected block "content"
body: <p>Even though I've got the blocks correctly addressed they aren't being brought into the layout page:</p>
  
  <pre><code>//- layout.jade
  doctype html
  html
    head
        title My Page
    body
      block content //- Main content goes here
  
  
  
  
  //- index.jade
  extends ./layout.jade
  
  block title
    title Article Title
  
  block content
    h1 My Article
  </code></pre>
  
  <p>I've since found the answer and think it should be documented to help others...</p>