Actually address the clamping issue.

Author: dbaron

css3-transitions/Overview.html

@@ -1149,9 +1149,11 @@ <h2 id=animatable-types><span class=secno>6. </span><a
    <i>V</i><sub>res</sub> = (1 - <i>p</i>) ⋅ <i>V</i><sub>start</sub> +
    <i>p</i> ⋅ <i>V</i><sub>end</sub>.
 
-  <p class=issue>Issue: Need to describe handling of out-of-range values that
-   can result from cubic-bezier(). Clamping values to the allowed range is
-   probably the best solution.
+  <p> However, if this value (<i>V</i><sub>res</sub>) is outside the allowed
+   range of values for the property, then it is clamped to that range. This
+   can occur if <i>p</i> is outside of the range 0 to 1, which can occur if a
+   timing function is specified with a <i>y1</i> or <i>y2</i> that is outside
+   the range 0 to 1.
 
   <p> The following describes how each property type undergoes transition or
    animation.

css3-transitions/Overview.src.html

@@ -1129,9 +1129,14 @@ <h2 id="animatable-types"><a id=animation-of-property-types->
           <i>p</i> &sdot; <i>V</i><sub>end</sub>.
       </p>
 
-      <p class="issue">Issue:  Need to describe handling of out-of-range
-      values that can result from cubic-bezier().  Clamping values to the
-      allowed range is probably the best solution.</p>
+      <p>
+        However, if this value (<i>V</i><sub>res</sub>)
+        is outside the allowed range of values for the property,
+        then it is clamped to that range.
+        This can occur if <i>p</i> is outside of the range 0 to 1,
+        which can occur if a timing function is specified
+        with a <i>y1</i> or <i>y2</i> that is outside the range 0 to 1.
+      </p>
 
       <p>
         The following describes how each property type undergoes transition or