> I think he wants to stop at the first following sibling that doesn't end in
> ",", 

perhaps, but (apart from the fact I can't spell select) I tried to
answer the question as asked not the question as perhaps intended.
(Admittedly doing the latter is probably more useful:-)

Just in case, here's a version answering that, again avoiding recursion
(even though recursion is good for the soul)

  <xsl:value-of select=".">
  <xsl:for-each select="following-sibling:*
         [contains(concat(.,'QWERTYUIOP'),',QWERTYUIOP')
         and
         preceding-sibling:*
           [contains(concat(.,'QWERTYUIOP'),',QWERTYUIOP')
              or not(preceding-sibling:*)]
           ]">
   <xsl:value-of select=".">
  </xsl:for-each>
 </xsl:template>

even less tested than last time

David

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