I Have a Cunning Plan (or, Making Money by Doing Good)

If you've ever posted an ad for a programmer, you'll know just how much haystack you have to sift through to find a few needles. At least half of the people who send in resumes cannot write a simple FizzBuzz program, and filtering the ones who can is always a headache (and a big drain on a company's technical resources, since most HR staff don't know enough about programming to do it themselves).

Enter Stack Overflow, the premier technical Q&A site on the interweb. Lots of people spend lots of time being helpful there, and smart companies have taken notice: I know of at least two that ask applicants for their SO scores as part of the resume-screening process. My question is, could companies outsource technical interviews to SO? More specifically:

1. A company wants to hire someone who can do some technical task program in Django, administer a large database, whatever.
2. They submit their request to SO, along with the candidate's contact info.
3. SO matches the request with someone who has a score over 1000 and has ticked the box saying "will interview people".
4. The candidate and the interviewer rendezvous on a private portion of the SO site at an agreed time. The candidate shares her desktop with the interviewer, and they can chat voice and text.
5. The technical interview takes place. Everything is recorded for C's HR department to review later.
6. The company pays a standard fee; SO keeps a commission, and passes the rest on to the interviewer.

Crucially, the candidate and interviewer don't know each other's identities: they both log in to SO to get connected, and since everything is recorded, HR will know if they gave each other a way to connect via another channel. That makes it hard (not impossible, but hard) for the two parties to conspire with each other, and that, plus a sufficiently large pool of interviewers, keeps the system trustworthy.

I've been interviewed this way (though I knew the identity of my interviewer), and it worked pretty well. It solves a real problem that a lot of companies face, and it gives people an incentive to keep being useful on SO (which I think is a good thing). Do you think it's workable? Or is there a variant that would work even better?