Using xsl variable to capture output of call-template returning blank for me

I have seen lots of posts that do something like this and that makes me feel like this is possible and I am just doing something wrong. I have simplified it as much as possible to try and figure out why this is happening:

Heres my xml (nothing very exciting):

<?xml version="1.0" encoding="UTF-8"?>
<REPORT>

</REPORT>

Here is my xsl:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
    <xsl:template match="REPORT">
      <xsl:variable name="tryThisTemplate">
        <xsl:call-template name="TRY_THIS"/>
      </xsl:variable>
      <TEST1>
        <xsl:call-template name="TRY_THIS"/>
      </TEST1>
      <TEST2>
        <xsl:value-of disable-output-escaping="yes" select="$tryThisTemplate" />
      </TEST2>
      <TEST3>
        <xsl:value-of select="$tryThisTemplate" />
      </TEST3>
    </xsl:template>

    <xsl:template name="TRY_THIS">
      <MY_NODE desc="my description" />
    </xsl:template>
</xsl:stylesheet>

Here is my result:

<?xml version="1.0" encoding="utf-8"?>  
<TEST1>
  <MY_NODE desc="my description"/>
</TEST1>
<TEST2></TEST2>
<TEST3></TEST3>

Here is my question: How come TEST2 and TEST3 don't work. The $tryThisTemplate variable appears to be blank. Am I misunderstanding something here. Should I be doing this in a different way?