Last paragraph is a hidden gem, should be pinned at the top of the page. Perhaps a blog post? :D
I was involved in hundreds of tech interviews in the past several years. So many times in discussing a candidate's performance, I found some of the interviewers' questions and comments were unrealistic, even preposterous. In one case, an interviewer gave a hard dynamic programming question. We were a tech company and had very good engineers. Our products and our technologies, however, rarely need dynamic programming skills of this difficult level. I couldn't bear it. So I asked, "who think he can solve this problem on the whiteboard in 40 minutes right now?" Dead silence.