I'm more of a designer than a developer, and when looking at the Arc example I have to ask how this matters in a real world example. How much extra code would it be to add classes on the links or form elements so they could be appropriately styled with CSS? The Arc code is short because it drops in HTML and nothing else, but that's not useful at all when actually creating and producing web applications.
Could someone rewrite the original Arc code with a form that has an ID, labels in the form for accessibility, and buttons & links with classes?