code: function() {
      var elThead = this._elThead;
      if(elThead) {
          var elTable = elThead.parentNode;
          Ev.purgeElement(elThead, true);
          this._destroyColumnHelpers();
          elTable.removeChild(elThead);
          this._elThead = null;
      }
  }
docs: Destroy's the DataTable THEAD element, if available.
  
  @method _destroyTheadEl
  @private