The navigation bar of that site to not stay put, vertically, when you click one of the links. That in itself undermines a lot of the author's message, as they

The navigation bar of that site to not stay put, vertically, when you click one of the links. That in itself undermines a lot of the author's message, as they were not able to reasonably de-framework themselves. (And - it's not hard to get the navbar right, in any number of ways. But you do have to do a bit of work before you preach things to others.)