LayoutTests/fast/forms/formmove.html

<form><input type=radio name="one">One
<input type=radio name="one">Two
<input type=radio name="one">Three

</form>

<form>

<input type=radio name="one">One
<input type=radio name="one">Two
<input type=radio name="one">Three
</form>

<script>
document.forms[1].appendChild(document.forms[0].firstChild); document.forms[1].appendChild(document.forms[0].firstChild);
document.write("The count of the # of elements in form 1 should be 2 and in form 2 should be 4.  The count in form 1 is " 
+ document.forms[0].elements.length + ", and the count in form 2 is " + document.forms[1].elements.length);
</script>