Angle brackets and string manipulation

Basic problem is that I had to resort to the always infamous
disable-output-escaping to substitute a <br /> for a marker character(s)
in a text() node string.  Did I happen upon an actual valid use of
d-o-e, or am I missing better way to do this?

During the transformation all text() nodes are checked for one or more
linebreak markers using the following template:
======================================================

<xsl:template match="text()">

  <!-- use a variable to allow additional substring substitions 
       not shown to simplify -->
  <xsl:variable name="t1">
    <xsl:call-template name="insert_breaks">
      <xsl:with-param name="source_string" select="."/>
      <xsl:with-param name="marker" select="'!br;'"/>
    </xsl:call-template>
  </xsl:variable>

  <xsl:value-of disable-output-escaping="yes" select="$t1"/>

</xsl:template>

======================================================


The insert_breaks template simply substitutes a "<br />" for the defined
linebreak marker passed as a parameter:
======================================================

<xsl:template name="insert_breaks">

  <xsl:param name="source_string" select="."/>
  <xsl:param name="marker"/>

  <!-- If $marker is in the $source_string -->
  <xsl:if test="contains($source_string,$marker)">	
    <!-- then replace it with "&lt;br /&gt;" and look for another -->
    <xsl:call-template name="insert_breaks">
      <xsl:with-param name="source_string">
        <!-- make the substitution by taking everything before the
             marker, insert the br element, and finish with everything
             after the break marker -->
        <xsl:value-of select="substring-before( $source_string,
                                                $marker )"/>
        <xsl:text>&lt;br /&gt;</xsl:text>
        <xsl:value-of select="substring-after( $source_string,
                                               $marker )"/>
      </xsl:with-param>
      <xsl:with-param name="marker" select="$marker"/>
    </xsl:call-template>
  </xsl:if>

  <!-- terminating case where the $marker is not found in the
       source string -->
  <xsl:if test="not(contains($source_string,$marker))">
    <xsl:value-of select="$source_string"/>
  </xsl:if>

</xsl:template>

======================================================


Without the d-o-e in the text() template, I get the the actual "&lt;br
/&gt;" in the resulting XHTML and rather than a line break in the
browser output, I see the actual "<br />" characters on the screen -- 
not what I want.  Bottom line question: Is outputing the results of a
string manipulation that inserts an element a (the?) valid use case for
d-o-e?

Other minor details that someone else may decide are major:
  MSXSL V4
  output method="xml"
  testing in XML Spy V4.3

Thanks.

-- 
Steve Rosenberry
Sr. Partner

Electronic Solutions Company -- For the Home of Integration
http://ElectronicSolutionsCo.com

(610) 670-1710

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list