Yes, @teh_g is correct, global moderators are special in that they will always have moderate privilege outside of the privileges page. Unfortunately it doesn't look as though you will be able to restrict gmods from their moderation privileges for this forum -- it's quite an odd use case!
Two notifications for one followed user and his post.
When there is new post and I follow the user and the topic, then 2 notifications appears.IMHO second line is just enough. cc @julian
for one post update