diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
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index a1f627c..b1ea466
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1
*** 5785,5790 ****
--- 5785,5804 ----
  
       <listitem>
        <para>
+        <function>to_timestamp</function> and <function>to_date</function>
+        exist to handle input formats that cannot be converted by
+        simple casting.  These functions interpret input liberally,
+        with minimal error checking.  While they produce valid output,
+        the conversion can yield unexpected results.  For example,
+        input to these functions is not restricted by normal ranges,
+        thus <literal>to_date('20096040','YYYYMMDD')</literal> returns
+        <literal>2014-01-17</literal> rather than causing an error.
+        Casting does not have this behavior.
+       </para>
+      </listitem>
+   
+      <listitem>
+       <para>
         Ordinary text is allowed in <function>to_char</function>
         templates and will be output literally.  You can put a substring
         in double quotes to force it to be interpreted as literal text