this looks great, thank you!  - the only downside is that the input to
this grouping attempt is a variable containing the input. So I fear I
can't use<template match="text">  here. I think I would need a new
transformation document in the pipeline with this attempt - which I
would love to avoid. - Or am I mistaken?

  <xsl:template match="test">
    <xsl:copy>
      <xsl:for-each-group select="*" group-adjacent="boolean(self::item)">
        <xsl:choose>
          <xsl:when test="current-grouping-key()">
            <xsl:sequence select="mf:group(current-group(), 0)"/>
          </xsl:when>
          <xsl:otherwise>
            <xsl:apply-templates select="current-group()"/>
          </xsl:otherwise>
        </xsl:choose>
      </xsl:for-each-group>
    </xsl:copy>
  </xsl:template>

	Martin Honnen
	http://msmvps.com/blogs/martin_honnen/