Change in response to issue #658

This small update addresses the issue #658 (Reflow Understanding text hard to parse when it talks about 1.4.4), proposing a different wording.

understanding/21/reflow.html

@@ -50,7 +50,8 @@ <h3>Avoiding scrolling in horizontally and vertically written languages</h3>
     	</section>
       <section>
  <h3>The relation of Reflow to the Success Criterion 1.4.4 Resize Text</h3>
-        <p>The focus of the Reflow Success Criterion is to enable users to zoom in without having to scroll in two directions. <a href="resize-text" class="sc">Success Criterion 1.4.4 Resize Text</a> also applies, so it should be possible to increase the size of all text to at least 200% while simultaneously meeting the reflow requirement. If text is reduced in size when people zoom in (or for small-screen usage), it should still be possible to get to 200% enlargement. For example, if text is set at 20px when the window is 1280px wide, at 200% zoom it should be at least 20px (so 200% of the default size), but at 400% zoom it could be set to 10px (therefore still 200% of the default 100% view). It is not required to achieve 200% enlargement at every breakpoint, but it should be possible to get 200% enlargement in some way.</p>
+        <p>The focus of the Reflow Success Criterion is to enable users to zoom in without having to scroll in two directions. <a href="resize-text" class="sc">Success Criterion 1.4.4 Resize Text</a> also applies, so it should be possible to increase the size of all text to at least 200% while simultaneously meeting the reflow requirement. If text is reduced in size when people zoom in (or for small-screen usage), it should still be possible to get to 200% enlargement.</p>
+        <p>For example, if at the default browser setting of 100% zoom, text is set at 20px when the window is 1280px wide, the same 20px at 200% zoom would mean a text size of 200%. At 400% zoom, the author may decide to set the text size to 10px: the text would now still be enlarged to 200% compared to the default browser setting of 100% zoom. It is not required to achieve 200% text enlargement at every breakpoint, but it should be possible to get 200% text enlargement in some way.</p>
       </section>
              <section>
       <h3>Browsers on mobile operating systems</h3>