Having done a degree in Psychology, such tests that NATS use to assess one's personality traits have been repeatedly found to be accurate and stem from personality gurus like Eysenck, McCrae and Costa (Google them to find out more!) They can certainly tell you more about an individual's personalit traits with those 'stupid, repetitive' questions than a 5 minute interview. What they also do is eliminate any unconscious bias by the interviewer based on anything from gender to body size to accent etc. (I think unconscious is important here, not saying that any interviewers are purposely biased!)
Also, intelligence isn't the be all and end all, if so, I could honestly say that any of my graduate friends could pass the seection process with ease but I know that they wouldn't have the specific traits that NATS are looking for.
Some may say I'm biased as I recently got through the selection process. However, it was my 2nd attempt as I failed 1st time round so I know how it feels to be rejected. Upon meeting a few of the HR people, it was emphasised that personality was important and there were specific traits that they were looking for which is understandable as there is absolutely no point in recruiting someone who doesn't show consistency or a hint of the aspects of personality that they are after.
I'll be quiet now
