PHP: seeded shuffle via usort

script.php

<?php

$dist = [];
mt_srand(1337);

for ($i = 0; $i < 10000; $i++) {
    $a = range('A', 'E');

    usort($a, function() { return mt_rand(-1, 1); });
    #shuffle($a);

    foreach ($a as $k => $v) {
        $dist[$v][$k+1] = ($dist[$v][$k+1] ?? 0) + 1;
    }
}

foreach ($dist as $v => &$a) {
    ksort($a);
}
ksort($dist);

echo <<<EOS
Given a list of five values, 'A' through 'E', if we shuffle them 10,000
times, we expect each value to appear in any given position about 2,000
times:


EOS;

var_export($dist);
echo "\n";

shuffle.txt

Output with shuffle (and thus no seed):

array (
  'A' => 
  array (
    1 => 2007,
    2 => 1959,
    3 => 1871,
    4 => 2046,
    5 => 2117,
  ),
  'B' => 
  array (
    1 => 2001,
    2 => 1979,
    3 => 2029,
    4 => 2005,
    5 => 1986,
  ),
  'C' => 
  array (
    1 => 2055,
    2 => 1981,
    3 => 1976,
    4 => 2022,
    5 => 1966,
  ),
  'D' => 
  array (
    1 => 2001,
    2 => 2088,
    3 => 2004,
    4 => 2014,
    5 => 1893,
  ),
  'E' => 
  array (
    1 => 1936,
    2 => 1993,
    3 => 2120,
    4 => 1913,
    5 => 2038,
  ),
)

usort.txt

Output with usort:

array (
  'A' => 
  array (
    1 => 5644,
    2 => 1541,
    3 => 1739,
    4 => 776,
    5 => 300,
  ),
  'B' => 
  array (
    1 => 1035,
    2 => 5788,
    3 => 2191,
    4 => 730,
    5 => 256,
  ),
  'C' => 
  array (
    1 => 2876,
    2 => 1694,
    3 => 3295,
    4 => 1549,
    5 => 586,
  ),
  'D' => 
  array (
    1 => 322,
    2 => 725,
    3 => 2009,
    4 => 4679,
    5 => 2265,
  ),
  'E' => 
  array (
    1 => 123,
    2 => 252,
    3 => 766,
    4 => 2266,
    5 => 6593,
  ),
)