All good points. At the end of the day, you have 45 minutes to make a recommendation as to whether a person will be a good fit for your company (and viceversa). It's never enough. I've always been more interested in the discussion that came out of this exercise than in the actual lines of code. The main data point is: how do people think and troubleshoot? And yes, also to your point, I hope interviewers remind themselves often than being on the "other" side has additional stress and we're never at our best, so adjust expectations accordingly!