I've interviewed candidates who can talk an amazing game but can't seem to code. Starting a couple of years ago at our organization, it has been required that candidates produce _something_ that can run (or come real close to it).
And yet, here we have this article, and a bunch of commenters who seem to think it's perfectly ok to not verify the main requirement of the position. It's madness!
Writing code is a process, few people can produce production quality code on the first go especially with someone looking over your shoulder.
If they haven't written code that they can share or that is Open Source, doesn't that really settle it?