# fold the scalar and aref into an array
my @table_gi_tr = listify $table{gi_tr} ;

# create an array containing HTML::Element pointers to the <tr> or <tr>s
my @iter_node = map 
    {
      $table->{table_node}->look_down($ID, $_)
    } @table_gi_tr;

# tie a scalar to the list of <tr> so that we can cycle thru 'em
tie $table->{iter_node}, 'Tie::Cycle', \@iter_node;

# iterate through the model data
 while (my $row = $table{tr_data}->($table, $table{table_data})) 
   {

      # pick out a <tr> to display the row of model data with:

      my $I = $table->{iter_node};   # force the tied data to FETCH into $I
      my $new_iter_node = $I->clone; # clone the dummy <tr> for templating

      # wont work:      my $new_iter_node = $table->{iter_node}->clone;

      ...

   }