I set the user to admin and she can post.
But is that normal?
Surely a blogger or priveliged blogger can post an article?

It's all about permissions. Either the individual blogger has to have permissions to post in a blog, or the group the blogger is in.

The only way I know how to make it work is this: go to 'Blog settings', pick the blog you want this person to post in, click on the 'Features' subtab. I think it is that one, but anyway find the subtab with a checkbox for "use advanced properties" at the bottom and check it then save the changes.

Now you will have two new subtabs - User perms and Group perms. There you will be able to make a User or a Group be a "member" of the blog you selected. You will also be able to set up all kinds of different levels of permissions for each user/group.