I know this, because I used to look at resumes and have long conversations before I ran my pairing interview. And I found the results almost uncorrelated. Now I save the fun conversations for people who make it through the screening. But by then I already know if I want to hire them.
My pairing interview (it's a pairing session, not a code challenge) covers aspects of engineering that I specifically care about. It's not terribly hard. But at the end I'll have a pretty good idea if I want to turn this person loose in my codebase.
To others reading along, I'm not talking about someone not being able to write a multitasking OS on their own. I mean, I'm not sure how these people possibly graduated college not knowing how to write a trivial program in the language of their choosing. Turns out you can get surprisingly far into a software engineering degree without every writing code. I wouldn't have believed it. Evidence proves it though.
The number of people with impressive looking resumes, and good command of the jargon, but who still can't successfully code hello world is shocking.
I don't believe you (general you, not just the parent) can even code until you demonstrate that to me, or until the industry comes up with a reputable way to tell me that you can code. Until then I'll be making sure you can at least write code that compiles and finishes a brain-dead simple task.