Allow removal of primary and secondary menus from blocks configuration

I'd like to open this issue, while i think it is mostly not the best idea to have primary and secondary menu visible in blocks configuration. This issue is opened in reference to http://drupal.org/node/171019. I know this behavior was the way how it has worked in past, but as a theme developer i know the people using the theme are trying to position the secondary menu with block configuration, however this is hardcoded in page.tpl.php or not.

What I'm said them is simple - "don't use block configuration to assign primary and secondary menus to a region" with the side note that "this are very special menu types that are already hardcoded in the themes". And this is why i think it's better to not allow this per default - or give theme developers the ability to disable visibility of primary and/or secondary menus via the themes .info file.