--- a/ttml1/spec/ttml1-changes.html	Sun Sep 01 13:25:39 2013 -0600
+++ b/ttml1/spec/ttml1-changes.html	Wed Sep 04 23:25:44 2013 -0600
@@ -93,8 +93,10 @@
   intermediate synchronic document.
 
 * In 8.2.12, improve compatibility with CSS and XSL-FO implementations by interpreting
-  'normal' line height as 120% (1.2 multiplier) of relevant font size instead of 100%
-  (1.0 multiplier).
+  'normal' line height as no less than the largest font size.
+
+* In 8.2.12, add a note recommending that 'normal' line height be interpreted as 125%
+  of the largest font size.
 
 * In 8.2.13, correct typo where "initial" value was written, but "computed" value
   intended.

--- a/ttml1/spec/ttml1.xml	Sun Sep 01 13:25:39 2013 -0600
+++ b/ttml1/spec/ttml1.xml	Wed Sep 04 23:25:44 2013 -0600
@@ -4567,10 +4567,16 @@
 </tbody>
 </table>
 <p>If the value of this attribute is <code>normal</code>, then the
-computed value of the style property must be considered to be the same
-as 120% of the largest font size that applies to the element and its
+computed value of the style property must be considered to be no less than the
+size of the largest font size that applies to the element and its
 descendant elements in the intermediate synchronic document as determined by
 <specref ref="semantics-region-layout-step-1"/>.</p>
+<note role="elaboration">
+<p>It is recommended that presentation processors use a computed line height that is
+125% of the size of the largest applicable font size when the value <code>normal</code>
+is specified. The choice of 125% allows use of a font size of <code>0.8c</code> in order
+to obtain a line height of <code>1c</code>.</p>
+</note>
 <p>If specified as a <loc
 href="#style-value-length">&lt;length&gt;</loc>, then the length must
 be non-negative.</p>