Use command-specific alias options when using a group alias

The following uses the watchdog-show command as an example but it applies to all commands.

With an aliases file, named test.aliases.drushrc.php, containing the following definitions

$aliases['group'] = array(
   'site-list' => array('@a', '@b',),
);

$aliases['a'] = array (
  'uri' => 'www.example.com.a',
  'root' => 'D:/web sites/drupal7',
  'command-specific' => array(
	'watchdog-show' => array('count' => '1',),
  ),
);

$aliases['b'] = array (
  'uri' => 'www.example.com.b',
  'root' => 'D:/web sites/drupal7',
  'command-specific' => array(
	'watchdog-show' => array('count' => '2',),
  ),
);

the following commands perform as expected, listing one and two log entries respectively.

drush @a watchdog-show
drush @b watchdog-show

However the following commands ignore the command-specific options in the alias file and list the default 10 log entries

drush @group watchdog-show
drush @test watchdog-show

The documentation in example.aliases.drushrc.php says

These options will only be set if the alias is used with the specified command

It would seem more helpful to me if these options were set when a group alias was used as well as when a site alias is used. If there is a reason why that is a bad idea then making clearer the limitations of group aliases would be good.