I don't disagree with anything you say. As I mentioned earlier that all people who hack such interviews do have basic understanding/skills requisite for the corp, quite enough to play the gymnastics of the interviews.

A good interviewer does try to gauge whether the answer was known to the interviewee. But I have seen that happen far more at hot startups than big companies- primarily because of their more stringent process which leaves less wiggle room for guess work and is more tuned towards concretely judged parameters.

I just don't like the facade of 'hiring the smartest people' in the world, when their mechanism largely filters just well-trained average people.

And I most certainly don't want to sound condescending, so I apologize before-hand. But I probably used a different definition of average than what you or most people here may have in mind. I know quite a few ACM ICPC world finalists, am a region finalist myself, and have conducted/ published CS research with reasonable impact. So I was simply using my PhD program peers as good, and people with lesser (proven) skills as average. My fault, but I hope you can see what I was trying to say.