Having done Gliders and PPL in civvy life I quickly learnt to avoid ex RAF instructors at an early age, the previously made point about "why can't you do this already" and "don't do it like that, do it like this" without actually telling you what "it" was meant I learnt where my training money would be wasted.
I am sure most of them are great and most of them have adapted to civvy life, I just wish I had met one of them.