<div id="typeDiv">
        <xsl:choose>
                <xsl:when test="1=1">
                </xsl:when>
        </xsl:choose>
</div>

Something about the above code is causing an elusive problem with the
HTML in my document. Removing the code removes the behavoir. The above
code, as far as I can tell, should have absolutely no output (although
it may have whitespace, someone else could tell me).

It creates an empty <div> and if you are using
Internet Explorer (you don't say) any properties
you have associated with that id that "bleed", as I've documented in:

In my case, the properties of the empty <div> are
applied to the remainder of the document.

if I place <xmp> inside the div, encapsulating the XSL, a quite
strange thing happens. The code for the close-div tag appears, as well
as the rest of the document after the div as though the XMP tag were
not closed.

What on earth is going on and is the culprit XSL?

If the problem you are experiencing is visual,
the problem is probably with the user agent
displaying the HTML ... if the problem you are
experience is that unexpected markup is showing
up in the result, the problem is probably with
your stylesheet ... if the problem you are
experiencing is not-well-formed markup is showing
up in the result, the problem might be the
processor.  From what you say, I doubt the problem is the XSLT specification.

--
UBL/XML/XSLT/XSL-FO training: Verx, Denmark 2006-10-02/06,11-20/24
UBL International 2006  2006-11-13/17 http://www.ublconference.com
World-wide corporate, govt. & user group UBL, XSL, & XML training.
G. Ken Holman                 mailto:gkholman@xxxxxxxxxxxxxxxxxxxx
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