Went through the HR screening process and was later scheduled to have a technical interview with one of their senior software engineers. The technical interview went over generic questions about design patterns like "what is polymorphism", etc. and later went on to use a collaborative text editor only to be asked to implement a binary search method. The description of the position listed PHP as the primary language and made no mention of any language were you would ever need to [re-]implement something like this, thus I ended the interview. Forming this same question as a pre-interview exercise would have been much more appropriate. I would never take a position where I had to solve difficult problems that require concentration while having someone breathing down my neck, and for the same reason I would never take a position that screens employees utilizing this setting. There is an unlimited list of programming concepts that one needs to selectively navigate depending on the requirements of the specific role or craft you want to work in/with. Asking questions that do not apply to that role during an interview is poor form. Test the knowledge and experience relative to the role instead of just trying to test what a candidate doesn't know (you'll pass up on plenty of great programmers). I've worked with plenty of people in the past that were better at reading technical articles and explaining design patterns while not knowing when and when not to apply them, much less being able to get work done in a reasonable time-frame.