unnecessary query on every node_load

In your node_load you do this:

function scheduler_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {

  // Run $op == load for any user.
  if ($op == 'load') {
    if (isset($node->nid) && $node->nid) {
      $result = db_query('SELECT * FROM {scheduler} WHERE nid = %d', $node->nid);
      if ($result) {
        $row = db_fetch_array($result);
        if (isset($row['nid'])) {
          unset($row['nid']);
          $node->publish_on = $row['publish_on'];
          $node->unpublish_on = $row['unpublish_on'];
          $node->timezone = $row['timezone'];
          $row['published'] = $row['publish_on'] ? date(variable_get('date_format_long', 'l, F j, Y - H:i'), $row['publish_on']) : NULL;
          $row['unpublished'] = $row['unpublish_on'] ? date(variable_get('date_format_long', 'l, F j, Y - H:i'), $row['unpublish_on']) : NULL;
          $node->scheduler = $row;
        }
      }
    }
  }

So every node_load a query is done whether or not that node type can have scheduler information. In your form_alter you have this (line 67):

if (variable_get('scheduler_'. $form['type']['#value'], 0) == 1) {

Why not do this for your nodeapi load too so you don't make unnecessary queries. Please change it to this:

function scheduler_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {

  // Run $op == load for any user.
  if ($op == 'load') {
    if (isset($node->nid) && $node->nid && variable_get('scheduler_'. $node->type, 0) == 1) {
      $result = db_query('SELECT * FROM {scheduler} WHERE nid = %d', $node->nid);
      if ($result) {
        $row = db_fetch_array($result);
        if (isset($row['nid'])) {
          unset($row['nid']);
          $node->publish_on = $row['publish_on'];
          $node->unpublish_on = $row['unpublish_on'];
          $node->timezone = $row['timezone'];
          $row['published'] = $row['publish_on'] ? date(variable_get('date_format_long', 'l, F j, Y - H:i'), $row['publish_on']) : NULL;
          $row['unpublished'] = $row['unpublish_on'] ? date(variable_get('date_format_long', 'l, F j, Y - H:i'), $row['unpublish_on']) : NULL;
          $node->scheduler = $row;
        }
      }
    }
  }

Applies to the 6.X-1.1 version too