[css-grid] Rephrase awkward paragraph defining named lines.

Author: tabatkins

css-grid/Overview.html

@@ -1384,21 +1384,18 @@ <h4 id=named-lines><span class=secno>5.1.1. </span> Named Grid Lines: the
    ‘<code class=css>(<var>&lt;ident></var>*)</code>’ syntax</h4>
 
   <p> While <a href="#grid-line"><i>grid lines</i></a> can always be referred
-   to by their numerical index, they can also be explicitly named in the
+   to by their numerical index, <dfn id=named-lines0 title="named line">named
+   lines</dfn> can make the <a
+   href="#grid-placement-properties"><i>grid-placement properties</i></a>
+   easier to understand and maintain. Lines can be explicitly named in the
    ‘<a href="#grid-template-rows"><code
    class=property>grid-template-rows</code></a>’ and ‘<a
    href="#grid-template-columns"><code
    class=property>grid-template-columns</code></a>’ properties, or <a
    href="#implicit-named-lines">implicitly named</a> by creating <a
    href="#named-grid-areas"><i>named grid areas</i></a> with the ‘<a
    href="#grid-template-areas"><code
-   class=property>grid-template-areas</code></a>’ property. Such <dfn
-   id=named-lines0 title="named line">named lines</dfn> can make the <a
-   href="#grid-placement-properties"><i>grid-placement properties</i></a>
-   easier to understand by allowing meaningful names in their values, and
-   easier to maintain if the grid definition changes in the future by tying a
-   grid item’s position to a stable name rather than a shifting numerical
-   index.
+   class=property>grid-template-areas</code></a>’ property.
 
   <div class=example>
    <p> For example, the following code gives meaningful names to all of the

css-grid/Overview.src.html

@@ -978,12 +978,10 @@ <h4 id='named-lines'>
 
 	<p>
 		While <i>grid lines</i> can always be referred to by their numerical index,
-		they can also be explicitly named in the 'grid-template-rows' and 'grid-template-columns' properties,
+		<dfn title="named line">named lines</dfn> 
+		can make the <i>grid-placement properties</i> easier to understand and maintain.
+		Lines can be explicitly named in the 'grid-template-rows' and 'grid-template-columns' properties,
 		or <a href="#implicit-named-lines">implicitly named</a> by creating <i>named grid areas</i> with the 'grid-template-areas' property.
-		Such <dfn title="named line">named lines</dfn> can make the <i>grid-placement properties</i> easier to understand
-		by allowing meaningful names in their values,
-		and easier to maintain if the grid definition changes in the future
-		by tying a grid item’s position to a stable name rather than a shifting numerical index.
 
 	<div class='example'>
 		<p>