Clarify and consolidate img ARIA allowances

This PR closes #424 and #452

Description of changes to come....

index.html

@@ -1527,7 +1527,10 @@ <h2 id="docconformance">
           </tr>
           <tr>
             <th id="el-img" tabindex="-1">
-              [^img^] with [^img/alt^]`="some text"`
+              <div class="correction proposed">
+                [^img^] with an accessible name. E.g., [^img/alt^]`="some text"` or as provided by other 
+                <a data-cite="html-aam-1.0#img-element-accessible-name-computation">`img` naming methods</a>
+              </div>
             </th>
             <td>
               <code>role=<a href="#index-aria-img">img</a></code>
@@ -1564,42 +1567,39 @@ <h2 id="docconformance">
             </td>
           </tr>
           <tr>
-            <th id="el-img-empty-alt" tabindex="-1">
-              [^img^] with [^img/alt^]`=""`
+            <th id="el-img-no-name" tabindex="-1">
+              [^img^] with no accessible name.
             </th>
             <td>
-              <code>role=<a href="#index-aria-presentation">presentation</a></code>
-            </td>
-            <td>
-              <p>
-                <a><strong class="nosupport">No `role`</strong></a> other than <code><a href="#index-aria-presentation">presentation</a></code>, which is NOT RECOMMENDED
-              </p>
-              <p>
-                <strong>No `aria-*` attributes</strong>
-                except <a data-cite="wai-aria-1.1#aria-hidden">`aria-hidden="true"`</a>.
-              </p>
-            </td>
-          </tr>
-          <tr>
-            <th id="el-img-no-alt" tabindex="-1">
-              [^img^] <a data-cite="html/images.html#unknown-images">without an `alt` attribute</a>
-            </th>
-            <td>
-              <code>role=<a href="#index-aria-img">img</a></code>
+              <div class="proposed correction">
+                <p id="el-img-empty-alt">
+                  If the `img` has an empty `alt` ([^img/alt^]`=""`) and lacks any other 
+                  <a data-cite="html-aam-1.0#img-element-accessible-name-computation">`img` naming methods</a>:<br>
+                  <code>role=<a href="#index-aria-none">none</a></code>, 
+                  <code>role=<a href="#index-aria-presentation">presentation</a></code>
+                </p>
+                <p id="el-img-no-alt" tabindex="-1">
+                  If the `img` <a data-cite="html/images.html#unknown-images">lacks an `alt` attribute</a> and lacks any other 
+                  <a data-cite="html-aam-1.0#img-element-accessible-name-computation">`img` naming methods</a>:<br>
+                  <code>role=<a href="#index-aria-img">img</a></code>
+                </p>
+              </div>
             </td>
             <td>
               <p>
-                If no <a data-cite="accname-1.2/#dfn-accessible-name">accessible name</a> is provided via other 
-                <a data-cite="html-aam-1.0#img-element-accessible-name-computation">`img` naming methods</a> (e.g., `aria-labelledby`, `aria-label`): 
-                <a><strong class="nosupport">No `role`</strong></a> other than <code><a href="#index-aria-img">img</a></code>, which is NOT RECOMMENDED.
+                <a><strong class="nosupport">No `role`</strong></a> other the roles 
+                <code>role=<a href="#index-aria-img">img</a></code>,
+                <code>role=<a href="#index-aria-none">none</a></code> or
+                <code><a href="#index-aria-presentation">presentation</a></code>, which are NOT RECOMMENDED.
               </p>
               <p>
                 <strong>No `aria-*` attributes</strong>
                 except <a data-cite="wai-aria-1.1#aria-hidden">`aria-hidden="true"`</a>.
               </p>
+
               <p>
                 Otherwise, if the `img` has an author defined accessible name, 
-                see <a href="#el-img">`img` with `alt="some text"`</a>.
+                see <a href="#el-img">`img` with an accessible name</a>.
               </p>
             </td>
           </tr>