Alred,
You missed the point, the poor guy was never suitable for the role. HQ 11 Gp posted the navigator internally within the Group AEW to AD. To save face Group Staff subsequently refused to accept a recommendation to suspend training a number of times. The chap always just made the grade with extra Sims and Flights on every phase. If a person has little or no aptitude for a task how long should you persevere with their training?
When lives may be put at risk its time to call it a day!