Like the RAF, more may be learned in the Crew room than the Class room.
I don't know about the RAF, but most of what I needed to learn about flying, I learnt on board of aircraft. From instructors and colleagues.
But I did try to mold their minds into the mind of a pilot.
Although I have been flying for more than 35 years (and instructing for over 20) I have no idea what "the mind of a pilot" might be. All I have encountered is a bunch of individuals who chose to fly aeroplanes (and gliders and hang gliders) out of their free will for a multitude of reasons and with a multitude of different aptitudes and mindsets. I call every one among them a pilot.