UI is just an implementation part. If the main point was to improve on the user interaction side, I missed it completely. Only things he provided were an idea roughly equivalent to the existing one and a shell script which needs to be run outside of the browser. It's hardly better than "pick one entry from the dialog box", however ugly that dialog box is.
No, the main point is to show how simple client verification actually is. This implementation is one step up on the application stack into a comfort zone which seems to be more acceptable by devs.
I believe in design in depth, and by allowing the most basic of techniques (form submission + cli tool stack) to handle something that is generally perceived as difficult and letting people "get" the manual process, the automation might not seem as daunting.
I did not intend to create a standard, just to provoke more discussion. I would however by gladly surprised if I woke up tomorrow and twitter allowed me to sign in by solving a challenge instead of a password : ).