What bothers me is that Ajax is "supposed" to be standards compliant, and obviously that is not.

Granted, I see no reason why that hack should not be a standard as it kinda makes sense. Its basically an anchor inside a plugin, rather than an anchor within the HTML. But it bothers me that sites might use something like that and make it essential for the site to work, when there should always be a fall-back.

I use HTML5 webkit/mozilla rounded corners on my site and a custom font, but it doesn't break anything if support is missing. Although I do not test my site in other browsers anywhere near as much as I should. Often find silly things broken in IE.