> I need the <thead> to close AFTER the 
> last <tr> (row) that contains <th> elements.

don't think of opening and closing tags, think of elements containing or
not containingg stuff.

reword the requirement to:

 I need the thead element to contain the result of processing rows that
have a th, and the remaining rows to be processed in tbody (or nothing,
I can't remeber quite how these tables worked). 

Once phrased that way, the translation to xslt is immediate:

<thead>
  <xsl:apply-templates select="tr[th]"/>
</thead>
<tbody>
  <xsl:apply-templates select="tr[not(th)]"/>
</tbody>


no xsl:if testing is required here, I think.

David

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