This works; I'm not having trouble, but I want to be certain that this is bulletproof.
I came up with a neat little .htaccess redirect, but I am not sure if it is secure; do you know?
RewriteRule ^goto/([a-z]+)/?$ /$1/ [R]
I think as long as the server is configured correctly and the files handle authentication autonomously, then it shouldn't be a security issue. Also, being that the rewrite rule only works with characters a-z and one slash I doubt they could jump around directories by injecting stuff into the URL I think...