The 'B' exam for promotion to Flt Lt was officially scrapped in May 1972. Thereafter, those who had not passed the exam but were 'time served' were promoted to the common seniority date of 8 May 72. Hence for many years afterwards the Air Force List contained lots of '8 of May Flt Lts'.
The reason for some 'closed book' questions was actually to test ones general understanding of the principles, rather than to deal with a precise case which, as said, would never take place in real life.
I used to enjoy some of the case studies in MAFL: 'R versus Buggins' etc. The best one for me was 'R versus oldduffer' where an airman procured a woman to have sexual intercourse with him on the premise that it would help to improve her breathing!!
Old Duffer