At the risk of cluttering up bandwidth does anyone know of another pilot in 2015 who was flying a commercial airliner, a Jet Provost, A Hawker Hunter and lastly a tailwheel light aircraft? It is a big ask to remain current and competent on 4 very different types given that some airliner groups like the Airbus can include three variants.
For example, in 2015 how many RAF Test Pilots were current on four types? A handful perhaps but, I doubt if any were also display qualified on two types which begs the question of why AH or the people regulating him thought this was an acceptable situation?
I'm not sure I buy that, apart from possibly confusing some limits/numbers etc. Some of the BBMF Bomber pilots have been current on 3, displaying 2 of them. Even current on 4 if you include the Chippie. Absolutely not an issue providing you put the correct 'cassette' in before you fly. Forgetting to put the gear down on the Dak 'cos you don't need to on the Chippie is a remote possibility, but the appropriate checks will always save the day.