xsl:apply-imports behavior wrong in Saxon?

I'm processing this simple document book.xml:
----------------------------------------------------------------------------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<book>
 <title>My book title</title>
 <para>My first para</para>
</book>
----------------------------------------------------------------------------------------------------------------------------

with this stylesheet (modetest.xsl):
----------------------------------------------------------------------------------------------------------------------------
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
 version="1.0">

<xsl:template match="book">
 <xsl:apply-templates select="." mode="inside_mode"/>
</xsl:template>

<xsl:template match="book" mode="inside_mode">
 <xsl:choose>
   <xsl:when test="$myflag != 0">
     <xsl:message>Reached apply-imports in modetest.xsl</xsl:message>
     <xsl:apply-imports/>
   </xsl:when>
   <xsl:otherwise>
     <xsl:message>Reached otherwise in modetest.xsl</xsl:message>
   </xsl:otherwise>
 </xsl:choose>
</xsl:template>

<xsl:template match="*" mode="inside_mode">
 <xsl:message>reached fallback in modetest.xsl for element
    <xsl:value-of select="local-name()"/></xsl:message>
</xsl:template>

</xsl:stylesheet>
----------------------------------------------------------------------------------------------------------------------------

And the imported no-mode.xsl stylesheet is:
----------------------------------------------------------------------------------------------------------------------------
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
 version="1.0">

<xsl:template match="book">
 <xsl:choose>
   <xsl:when test="$myflag != 0">
     <xsl:message>Reached when in no_mode.xsl</xsl:message>
     <xsl:apply-imports/>
   </xsl:when>
   <xsl:otherwise>
     <xsl:message>Reached otherwise in no_mode.xsl</xsl:message>
   </xsl:otherwise>
 </xsl:choose>
</xsl:template>

</xsl:stylesheet>
----------------------------------------------------------------------------------------------------------------------------

When I apply modetest.xsl to book.xml using xsltproc, the message output is
just:

Reached apply-imports in modetest.xsl
reached fallback in modetest.xsl for element title
reached fallback in modetest.xsl for element para

According to Saxon author Michael Kay's website, his description of
xsl:apply-imports is:

"The effect is to search for a template that matches the current node and
that is defined in a stylesheet that was imported (directly or indirectly,
possibly via xsl:include) from the stylesheet containing the current
template, and whose mode matches the current mode. If there is such a
template, it is activated using the current node. If not, the call on
xsl:apply-imports has no effect."

There is no template matching on book in mode="inside_mode" in the imported
stylesheet, so the call on xsl:apply-imports should have no effect.  That is
what I see when I process with xsltproc.  However, Saxon continues
processing the children of book in that mode, even though there is no
xsl:apply-templates to trigger such processing.   Why is Saxon applying
templates in mode="inside_mode" to the children of book?

Bob Stayton
Sagehill Enterprises
bobs@xxxxxxxxxxxx