Also-Control:

Also-Control: 欄 (ネットニュース)

6.15. Also-Control (制御もする。)

          The Also-Control header content marks the article as being a
          control  message IN ADDITION to being a normal news article,
          and specifies the desired actions:
               Also-Control-content = Control-content
          An article with an Also-Control header is filed  and  passed
          on  normally,  but the content of the Also-Control header is
          processed as if it were found in a Control header.
               NOTE: It is sometimes desirable to piggyback  con-
               trol  actions  on  a  normal  article, so that the
               article will be filed normally but  will  also  be
               acted  on  as  a  control message.  This header is
               essentially a generalization of Supersedes.

NOTE: Be warned that some old relayers do not implement Also-Control.

参考: 古い中継者は Also-Control を実装していないことに注意せよ。

An article with an Also-Control header MUST not have a Control or Supersedes header.

Also-Control 頭のついた記事は Control 頭や Supersedes 頭も つけてはいけません

[1] draft-usefor-articleにより廃止

usefor-article は、新しい代理者(の実装者)は無視するべきとしています。