I may have missed something, but I can't see why the following doesn't work:

<xsl:variable name="root" select="/"/>
<xsl:for-each select="doc('startingElements.xml')/element">
  <xsl:variable name="path" select="string(.)"/>
  <xsl:for-each select="$root/saxon:evaluate($path)">
    <xsl:result-document href="chunk{position()}.xml">
      <xsl:copy-of select="."/>
    </
  </
</

with a bit of elaboration to put leading zeros in the filename, etc.

<xsl:variable name="new-chunk-number"
  select="count(preceding-sibling::*[exists(my:chunk-started-by(.)] + 1"/>

Cheers,
Wendell

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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
17 West Jefferson Street                    Direct Phone: 301/315-9635
Suite 207                                          Phone: 301/315-9631
Rockville, MD  20850                                 Fax: 301/315-8285
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  Mulberry Technologies: A Consultancy Specializing in SGML and XML
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