No, he didn't. He wrote:
Code:
<div class="scene-break"/>
Which has no content. Inserting a paragraph and/or a non-breaking-space is adding content which is not contained in the original document.
The
div above doesn't add anything and can be displayed (or not) in any manner that CSS describes. The structure is marked up in his example, but the display of a blank line is not forced.
If someone wanted to display scene breaks with a set of diamonds, or asterisks or a horizontal line or an image of a giant dinosaur, there would be no way to do it in any example that contains a plain paragraph, or a plain line break.