This is an old site. Copyright of the site is 2012. The github repo's first commit[1] predates the first commit of Web Components' draft of Custom Elements[2] by a few months.

So, I wouldn't say ignorant but that the Web is catching up to this "spec's" vision.

[1] https://github.com/OscarGodson/HTML6/commit/7d58a98b30fe473d... [2] https://github.com/w3c/webcomponents/commit/c60060999073e181...