MooTools plugin - Remove all underlying text nodes of an element

Element.implement({
 // Removes all underlying text nodes
 removeTextNodes: function( startNode ){
  var initialNode = this || startNode;       
     var childList = initialNode.childNodes;
     if( childList.length === 0 ){ return; }
     
     // Walk through all childNodes. If text - remove, else search/destroy
     // potentially underlying text nodes
     var currentNode;
     var nodesToRemove = [];
     for( var i = 0, len = childList.length; i < len; i++ ){      
      currentNode = childList[i];
      if( currentNode.nodeName === '#text' ){ nodesToRemove.push( currentNode ); }
      else { Element.removeTextNodes( currentNode ); }
     }
     
     // When all text nodes on the current level are found, remove them from the DOM
     for( i = 0, len = nodesToRemove.length; i < len ; i++ ){
      currentNode = nodesToRemove[i];
      currentNode.parentNode.removeChild( currentNode );
     }
     
     return this;
 }
});

I use this to clear/update a label that only contains a field and text. E.g.
<label id="label-with-field"><input type="radio">Some text<label>

$('label-with-field').removeTextNodes().appendText('newLabel')

The last line in the method, "return this;" makes the method chainable.