[css-fonts-4] Refered to Cascade 5 for reset-only sub-property, rather than defining independently; fix #11904

Author: svgeesus

css-fonts-4/Overview.bs

@@ -1800,8 +1800,8 @@ Shorthand font property: the 'font' property</h3>
 	and their interaction with the 'font!!property' property:
 
 	<dl>
-		<dt><dfn>Set Explicitly</dfn></dt>
-		<dd><p>These properties may be set using the 'font!!property' property:</p>
+		<dt>Set Explicitly</dt>
+		<dd><p>These longhand properties may also be set using the 'font!!property' shorthand property:</p>
 			<ul>
 				<li>'font-family!!property'</li>
 				<li>'font-size!!property'</li>
@@ -1813,8 +1813,9 @@ Shorthand font property: the 'font' property</h3>
 				<li>'line-height'</li>
 			</ul>
 		</dd>
-		<dt><dfn>Reset Implicitly</dfn></dt>
-		<dd><p>These may not be set, but are reset to their initial values:</p>
+		<dt>Reset Implicitly</dt>
+		<dd><p>These properties are a [=reset-only sub-property=] of the 'font!!property' property 
+			and thus may not be set, but are reset to their initial values:</p>
 			<ul>
 				<li>'font-feature-settings!!property'</li>
 				<li>'font-kerning!!property'</li>
@@ -1831,8 +1832,10 @@ Shorthand font property: the 'font' property</h3>
 				<li>'font-variation-settings!!property'</li>
 			</ul>
 		</dd>
-		<dt><dfn>Cascaded Independently</dfn></dt>
-		<dd><p>There are neither set nor reset by the 'font!!property' property:</p>
+		<dt>Cascaded Independently</dt>
+		<dd><p>These (despite the property name starting with "font-") 
+			are not [=shorthand properties=] 
+			and thus are neither set nor reset by the 'font!!property' property:</p>
 			<ul>
 				<li>'font-palette!!property'</li>
 				<li>'font-synthesis-weight!!property'</li>