'Once Upon A Time,' or 'Degree Absolute' as was the episode's original title. It's the ultimate test which the President said No.6 had survived. In this episode No.6 is put through yet another ordeal, that of Degree Absolute, a recognised method, used in pshycoanalysis. The patient must come to trust his doctor, sometimes in extreme cases, they change places. That is a risk. So I've a mind that No.6 was not the only one being put to the test!