Hi Webnerd,
One way of doing this would be to add all the posts of a particular author to a category manually, then display the appropriate category when the user is logged in.
If you put every posts into a category named after each user’s numerical ID, the code would look a little like this (the code hasn’t been tested):
<?php if( function_exists('get_latex_url')
&& $user_id = get_current_user_id()
&& $user_latex_url = get_latex_url( 'term', $user_id, 'category' ) ): ?>
<a href="<?php echo $user_latex_url ?>">PDF of logged in user's posts</a>
<?php endforeach; ?>
This was based on the code in the FAQ.
You could modify the plugin to collate a user’s posts in the same way it collates categories and tags. This would require rather more skill and effort right now, but would save you from having to manually put posts into categories. I don’t intend to add anything to this plugin, so I won’t make this change myself.