A really deep Drupal conditional to hide Manage Display (display suite)

mymodule.php

<?php
/**
 * Selectively hide the "Manage Display" local task added by Display Suite
 * @see hook_menu_local_tasks_alter
 */
function HOOK_sitewide_tweaks_menu_local_tasks_alter(&$data, $router_item, $root_path) {
  // If we're on a node page
  if (isset($router_item['path']) && $router_item['path'] == 'node/%') {
    // If page_arguments exists
    if (isset($router_item['page_arguments']) && is_array($router_item['page_arguments'])) {
      // If tabs array exists
      if (isset($data['tabs']) && is_array($data['tabs']) && is_array($data['tabs'][0])) {
        // If tabs output array exists
        if (isset($data['tabs'][0]['output']) && is_array($data['tabs'][0]['output'])) {
          // Iterate through tabs to find the Manage Display tab
          foreach ($data['tabs'][0]['output'] as $k => $tab) {
            if ($tab['#link']['path'] == 'node/%/display') {
              unset($data['tabs'][0]['output'][$k]);
            }
          }
        }
      }
    }
  }
}