My understanding about author archive page URL rewriting is that as long as the author has atleast one post/page the URL for the archive page ofthe author will be re-written to:
http://mysite.com/author/%authorname%
However, if the author does not have any post/page then the URL for the archive page will be of the form
http://mysite.com/?author=id
How can we force wordpress to always rewrite the URL to /author-base/%author% even if the author does not possess any post/page.
We managed this by hijacking the default author template and setting up our own.
Set up a new url rewrite for team members:
In the template we then use:
to get the user’s id.
From there you can build out your own template (author.php) for your authors.
We approached this from the perspective of wanting a custom template and url structure for our authors, but ended up solving your problem in the process (I think).