Using a knife and fork with which to eat ones sandwiches and cakes for afternoon tea should not present a problem.
Mental image of P-N tucking into his inflight sarnies with a knife and fork, napkin decorously draped down the front of his immersion suit!
No, sorry - can't see it
Wander 00 - best things on the menu at Seletar officers' mess in 1967 were the cucumber sandwiches at afternoon tea, cut just as you described.
Last days of Empire!