Token argument help only available for multiple Viewfields

I was puzzled not being able to get the token help for setting arguments in a Viewfield until I found that it worked as soon as I set the field to multiple.

I actually found in viewfield.module line 263

 if ($token_enabled && ($field_settings || !$field['multiple'])) {
      $element['token_help'] = _viewfield_get_token_help($field);
    }

In really don't understand this condition for token help as tokens work perfectly with single fields: I just took note of the token I needed switched back to single, forced field and set my argument that worked on the spot.

Am I missing something or is this a bug?