Candidates always optimize for what is being interviewed, never ever forget that. The moment you put down a interview 'process' its all over. Doesn't matter what that process is, doesn't matter how difficult that is. Once you do it, its only a matter of recognizing patterns. Then all you have to do is develop a elaborate process to game it. A couple of months of practice is all it takes to do that.

The Steve Yegge, 'Get that job at Google' article is nothing but a 'Game this interview' article. Read this book, practice this X times and you shall get through. For heaven's sake, Do people hire for getting job done everyday or playing some puzzles from some book not even remotely relevant to any thing you will ever do on your job.

Companies like these want the best of the best people. Yet their methods completely revolve around knowledge and fact based questions. And sorry I don't believe asking difficult questions make it any better. There are forums on the net dedicated to train you crack such questions.

How many interviews check if candidates can last tough on the job situations? How many check if the candidate is hard working, How many check the candidates appetite to work on tough challenging time pressing projects? How many check if the candidate is innovative? Or checks a candidates general abilities like gumption, persistence or general appetite for work and delivering.

These companies often speak on how difficult it is to hire good people and then purposefully invent processes to avoid hiring such people.