О фиктивном тексте (о версиях, которые Питер указывает на ссылку), давайте посмотрим комментарии к файлу common.inc в папке drupal / includes:
function drupal_get_js($scope = 'header', $javascript = NULL) {
..
// A dummy query-string is added to filenames, to gain control over
// browser-caching. The string changes on every update or full cache
// flush, forcing browsers to load a new copy of the files, as the
// URL changed. Files that should not be cached (see drupal_add_js())
// get time() as query-string instead, to enforce reload on every
// page request.
$query_string = '?'. substr(variable_get('css_js_query_string', '0'), 0, 1);
..
}
function drupal_get_css($css = NULL) {
..
// A dummy query-string is added to filenames, to gain control over
// browser-caching. The string changes on every update or full cache
// flush, forcing browsers to load a new copy of the files, as the
// URL changed.
$query_string = '?'. substr(variable_get('css_js_query_string', '0'), 0, 1);
common.inc
..
}