title: What effect does the new precompile during publishing option have on MVC4 applications?
body: <p>So I recently updated Visual Studio 2012 to Update 2. Lo and behold, the next time I go to publish my application (via File Publish in this case) I notice that there are three new options:</p>
  
  <ol>
  <li>Delete all existing files prior to publish</li>
  <li>Precompile during publishing (with a link to Configure)</li>
  <li>Exclude files from the App_Data folder</li>
  </ol>
  
  <p>The first and third options are pretty self-explanatory, but I can't find any documentation on the second option as it applies to MVC. When I check it, there doesn't seem to be any change in the files produced on the site and I don't see any real change in performance.</p>