Earlier quoted context omitted.
I'm saying it produces false positives. False negatives are ok for a conservative hiring process, because you're paying for a super low false positive rate with a higher budget for false negatives. But the whiteboard hazing produces too high a rate of false positives -- candidates who can recite CS trivia, study in a way tailored and overfitted to the interviews, and then pass them and be hired even if they don't act…
It's not a false positive if they aren't testing for the thing that turns out to be positive. That people express creativity or whatever, despite making it through an employment filter based almost solely on technical concepts. It's just luck.
I'm saying that they view the riddles, data structure hazing, etc., as tests for quality X (where X == careful engineer who won't inject N^2 complexity into something and make it take centuries).
But really, the puzzles and so forth do not select for that X. You get people who are good at the trivia, but who still otherwise would inject poor complexity. Meanwhile, you reject people who might be careful and pragmatic, but are not talented at the trivia.
From their perspective (since they believe it does test for X) it produces false positives.