Use the standard design pattern of an identity template plus an overriding template:
<xsl:template match="node()">
<xsl:copy>
<xsl:copy-of select="@*"/>
<xsl:apply-templates/>
</xsl:copy>
</xsl:template>
<xsl:template match="comment()" priority="2"/>
Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference