its seems like giving a rocket science lesson more than just an interview.... that's why there are a huge amount of managers sucks in management level.
a bunch of rubbish. there is a reason why many business stop hiring these ppl for interview, because we are discovering that body language really doesn't matter if we are employing a technical role, the skills is even more important, we have hired that ppl looks professional representable but they can't do they jobs. these interview only really works if it is 1) low skill level jobs, 2) frontend interpersonal roles: sales/customer service, 3) management: got to look the part in front of the other employee. sometimes, the best looking and confident looking dude doesn't know what he is going to do in his technical jobs. so , just bare in mind, what job are you getting into.