Lots of people do poorly in whiteboard situations. As an employer, you may assert that you don't want any of them, fine. But I don't see the problem in giving people the option of using an alternative testing process.
This isn't "an alternative testing process" as such.
> To solve the problem of interview anxiety, we're adding a second track to our interview process at Triplebyte. Applicants, if they choose, will be able go through our process by completing programming projects on their own time.
> The project-based track will require a larger time commitment (and we expect lots of people to stick with the standard track for this reason).
I prefer an interview system where the company and the candidate both care. Commitment is a requirement for everyone.
The problem with them is fundamental: "You will only get someone desperate enough to take your exam."
If the person is qualified they will be swimming in opportunities and will likely throw your exam directly in the trash heap. If they aren't you probably don't want them working for you. I suppose these might work if the entire industry colluded on it but then ... prisoner's dilemma.
Maybe a more useful indicator is weeding out the candidates that didn't say "no thanks." Cause really why are they so desperate for a job and why do they have all this free time? but then ... ethics.