I read through the documentation, the manuals, and the source. I couldn't find any mention of legend. From my vantage point, I think that FormHandler will ignore legend, regardless of whether you try to enter it or not:). I tried entering legend with this script, but no luck.

#!/usr/bin/perl

use strict;
use warnings;
use HTML::FormHandler::Moose;
extends 'HTML::FormHandler::Model::DBIC';
use namespace::autoclean;

my $form = HTML::FormHandler->new( field_list => 
   [ authors =>  { type => 'Multiple', 
                   label_column => 'last_name', 
                   legend => 'first_name',
                   required => 1 }  ] );
$form->process();
print my $rendered_form = $form->render;
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