Unexpected warnings re-enabled

gistfile1.pl

#!/usr/bin/perl

# at the top of all of our code
use ourperl;
# this does this
#
# use Import::Into;
# use strict;
# use warnings;
# use experimental ();
# sub import {
#     my $caller_level = 1;
#     strict->import::into($caller_level);
#     warnings->import::into($caller_level);
#     experimental->import::into( $caller_level, 'signatures', 'postderef' );
#     
# }

# then we do this, which turns back on the warnings
use Mojolicious::Lite;

# then this unexpectedly gives us the warning:
# The signatures feature is experimental at test.pl line 24, <DATA> line 2231.
sub foo($bar) {
    say $bar;
}

1;