How to dynamically insert HTML from XSLT into document?

Here is a fragment of my code that is working:

  processor.importStylesheet(xslNode);

  var xmlNode = (new DOMParser()).parseFromString(
    '<?xml version="1.0"?>'
      +'<document>'
        +'<x name="x">x</x>'
        +'<y name="y">y</y>'
        +'<z name="z">z</z>'
      +'<abc>'
        +'<def>def</def>'
      +'</abc>'
      +'</document>', "text/xml");
  var newDocument = processor.transformToDocument(xmlNode);
  xslTarget.innerHTML = (new
XMLSerializer()).serializeToString(newDocument);


This seems terribly inefficient to take the DOM resulting from the XSLT and
convert it to a string only to parse it again when it is stuffed into the
innerHTML. Is there a simpler way? Perhaps I could just add "newDocument" as
a child of xslTarget? Does anyone have an example of better way of
displaying the result of a XSLT?

Also, is there a better way to load xml (than what I have done above) since
Martin Honnen is discouraging me from using XML data islands? I suppose I
could load an XML file from the server. Are there any other alternatives to
data islands?

Thanks,
Siegfried