And one added bonus: With your method, the clients have to deselect the nav bar every time they visit the site afresh. With cookies, they deselect the nav bar once and it's done for the life time of the cookie. But feel free to ignore that little fact.
Strangely enough, I don't see my user identifier in the URI of this page and yet the forum knows who I am. Even when I close the browser in between visits.
I wonder how that is done... clearly you just don't like to admit that you're wrong.
edit: I just looked at the tutorial you gave him... Great.
PHP Code:
document.cookie = "whatever";
whatever = document.cookie;
versus
<snip>
Yeah, so much easier and less lines of code :)