While I have some empathy, and I am not certain what was involved in your technical interview but the level of difficulty in some cases is just plain nuts. My first tech interview in January was mind boggling, timed questions of 90 seconds. The position was for Django, and not a single question was Django. All pure Python. The main question was so abstract to this day I have no idea wtf they wanted, 12 minutes to solve. Twitter and other places are filled with cases like this. So in an environment like this expect pinch hitters.

On a more positive note my last interview was very fair and on topic.