I read the article, and I don't think the two are mutually exclusive.
The author defines usable as requiring less effort, being more intuitive, being more "learnable", and being "more powerful" in that you can "do more with it faster".
He defines something with a good user experience as evoking an emotional response via sensory input: color, layout, structure, sound, graphics, content, etc.
You can certainly have both at the same time, or neither or only one for that matter. I don't see why it's a "battle" between one or the other.
If you like grunge-style sites, you could design one that hit all the right emotional buttons, from the colors to the fonts to the images to the branding to the content, and also have it highly usable, with clear navigation, unobtrusive use of flash and javascript, excellent textual and visual cues to help guide and assist the visitor, and more.
By the same token, you could have a completely unbranded, flat and visually bland site which also happens to be a usability nightmare: unclear menus, "mystery meat" graphical navigation (as Vince Flanders calls it), poor forward/backward link handling, and more.
k10k.net is an example of a highly usable and navigable site with a great user-experience factor. On the flip side is so-called usability expert Jakob Nielsen's very own site (useit.com): bland and unattractive (ostensibly for simplicity sake) but also hard to comprehend, use and navigate.
Those are only two of many examples which show how you can have both (or neither) at once.
Oh, and the author's road analogy is terrible. It's actually been proven that straight roads are NOT more usable; they lead to white-line fever and hence more accidents. You need some gentle curves and changes to keep the driver focused.
IMHO the author decided that he wanted to write about the idea of a conflict between usability and user experience, and then did everything he could to make the data fit his thesis.