--- a/ttml2/spec/ttml2.xml	Mon Jan 05 11:58:25 2015 -0700
+++ b/ttml2/spec/ttml2.xml	Mon Jan 05 12:14:49 2015 -0700
@@ -8963,7 +8963,7 @@
 </tr>
 <tr>
 <td><emph>Percentages:</emph></td>
-<td>see prose</td>
+<td>N/A</td>
 </tr>
 <tr>
 <td><emph>Animatable:</emph></td>
@@ -8976,19 +8976,11 @@
 span.</p>
 <p>The value <code>normal</code> corresponds to specifying a <loc href="#style-value-length">&lt;length&gt;</loc> value of zero (0),
 i.e., neither expand nor compress adjacent glyph spacing.</p>
-<p>If a <loc href="#style-value-length">&lt;length&gt;</loc> value is expressed as a positive scalar (not a percentage),
+<p>If a <loc href="#style-value-length">&lt;length&gt;</loc> value is expressed as a positive scalar,
 then the spaces between adjacent glyphs are expanded by an additional amount equal to that scalar value.
 If expressed as a negative scalar,
 then the spaces between adjacent glyphs are compressed by an additional amount equal to that scalar value, possibly resulting
-in overlapping glyph areas, up to a maximum amount that results in the origin of a subsequent glyph being equal to the
-origin of its preceding glyph.</p>
-<p>If a <loc href="#style-value-length">&lt;length&gt;</loc> value is expressed as a percentage, then that
-percentage is to be interpreted as relative to the value implied by <code>normal</code> letter spacing.
-Negative percentage values are not permitted.</p>
-<note role="example">
-<p>For example, a value of 100% is interpreted as equal to <code>normal</code> letter spacing, while
-50% is interpreted as half of normal letter spacing and 200% is interpreted as double normal spacing.</p>
-</note>
+in overlapping glyph areas, up to a maximum amount that results an effective advance of zero (0).</p>
 <p>If a computed value of the letter spacing associated with this attribute is not supported,
 then a <loc href="#terms-presentation-processor">presentation processor</loc> must use the closest supported value.</p>
 <note role="elaboration">