Every article has a dynamic search author link in What's Related, so i
hacked every mention of "/search.php?mode=search&type=stories&author=idnumber"
into
/searchauthor/search/stories/idnumber/
Then created a new folder called searchauthor and then created a .htaccess document in this new folder.
the Mod_Rewrite rules in this doc are:
RewriteBase /searchauthor/
RewriteEngine on
RewriteRule ^(.*)/(.*)/(.*)/$ /search.php?mode=$1&type=$2&author=$3