I have and it's not. Or, at least, it's not faster. But it's also more general purpose.

my $op = '+';
my $add_5_things = arbitrary_operator_maker($op, 5);

my @list_5 = (1..5);

timethese(1000000, {
  'add_5_things elements cached' => sub {
    $add_5_things->(@list_5);
  },
  'add_5_things elements dispatched' => sub {
    my $add_5_things = arbitrary_operator_maker($op, 5);
    $add_5_things->(@list_5);
  },
  'multi_add 5 elements' => sub {
    multi_add(@list_5);
  },
  'reduce' => sub {
    reduce { $a + $b} @list_5;
  }
});

Benchmark: timing 1000000 iterations of add_5_things elements cached, 
+add_5_things elements dispatched, multi_add 5 elements, reduce...
add_5_things elements cached:  0 wallclock secs ( 0.99 usr +  0.00 sys
+ =  0.99 CPU) @ 1010101.01/s (n=1000000)
add_5_things elements dispatched:  2 wallclock secs ( 2.94 usr + -0.00
+ sys =  2.94 CPU) @ 340136.05/s (n=1000000)
multi_add 5 elements:  2 wallclock secs ( 2.52 usr +  0.01 sys =  2.53
+ CPU) @ 395256.92/s (n=1000000)
    reduce:  4 wallclock secs ( 3.24 usr +  0.01 sys =  3.25 CPU) @ 30
+7692.31/s (n=1000000)

[download]

Or, with a bigger set:

my $op = '+';
my $add_500_things = arbitrary_operator_maker($op, 500);

my @list_500 = (1..500);

timethese(10000, {
  'add_500_things elements cached' => sub {
    $add_500_things->(@list_500);
  },
  'add_500_things elements dispatched' => sub {
    my $add_500_things = arbitrary_operator_maker($op, 500);
    $add_500_things->(@list_500);
  },
  'multi_add 5 elements' => sub {
    multi_add(@list_500);
  },
  'reduce' => sub {
    reduce { $a + $b} @list_500;
  }
});


Benchmark: timing 10000 iterations of add_500_things elements cached, 
+add_500_things elements dispatched, multi_add 5 elements, reduce...
add_500_things elements cached:  1 wallclock secs ( 0.72 usr +  0.00 s
+ys =  0.72 CPU) @ 13888.89/s (n=10000)
add_500_things elements dispatched:  0 wallclock secs ( 0.74 usr +  0.
+00 sys =  0.74 CPU) @ 13513.51/s (n=10000)
multi_add 5 elements:  0 wallclock secs ( 1.03 usr +  0.00 sys =  1.03
+ CPU) @ 9708.74/s (n=10000)
    reduce:  1 wallclock secs ( 1.18 usr +  0.00 sys =  1.18 CPU) @ 84
+74.58/s (n=10000)

[download]

Of course, it's also much more general purpose than the arbitrary_operator_maker is, which is highly specialized. But for these tests, though, reduce was the slowest of the bunch. Benchmarks are your friend.