More confusing...

In my 'play' site, I found that logged on as webmaster, if I posted a news article and did not approve it I could then not go back and approve it!

I went to the news preferences and set the option to allow authors to edit their own posts.

After that, the webmaster user could edit and approve all posts.

Now.... back to my main site... where it all works as it should....

the allow authors to edit their posts is NOT switched on so this is not the complete answer but it may get things working for you.