<p>I'm building the HTML code within an XML DOM object to be used as the contents of the innerHTML of a div element using an XSL template. Traditionally we create a new XML DOM document and add the input parameters as XML Elements for the transform via javascript. This is all very time-consuming as we are basically hand picking the data from another XML document that represents our current account and copying the data into a transient XML DOM document. </p>

<p>What I'd like to do is clone the relevant node of the account document (i.e. customer info) and use it as the basis for the transform. I don't want to use the account document directly as I'd like to be able to add transform specific input, without making changes to the account object.</p>

<p>How efficient is using .cloneNode(true) for a desired node of about typically less than 200 elements from a document of typically 2000+ elements? The target platform is IE6 with no external tools (i.e. ActiveX).</p>

IE will fail on certain things.
e.g. checked radio/checkboxes will not be checked when you add your copy to the DOM.
Example:
http://webbugtrack.blogspot.com/2008/03/bug-199-cant-clone-form-element-in-ie.html
http://webbugtrack.blogspot.com/2007/08/bug-242-setattribute-doesnt-always-work.html
To see what IE will actually return, try replacing the url with this in the Address Bar of one of your pages, and press enter.
```
```
javascript:'<xmp>'+window.document.body.outerHTML+'</xmp>';
```
```
If you are happy with the results, great!, but I think you'll end up less than satisfied at what IE returns (both in the DOM, and this "string" value equivelant.