but holy crap coderef!

That case isn't really equivalent to the others - the exported and fullname cases have an extra sub { } wrapped around them.

use warnings;
use strict;
use Benchmark qw/cmpthese/;
sub foo { 1+2==3 }
cmpthese(1e8, {
    one => \&foo,
    two => sub { foo() },
});

__END__

          Rate  two  one
two 24271845/s   -- -72%
one 86956522/s 258%   --
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