But it also ensures a basic minimum technical knowledge, above that of PPL level, so when students ask the slightly more in depth questions the instructors level of knowledge is above that found in the PPL text books.
So an experienced PPL isn't likely to have expanded his/her knowledge over the years since passing their PPL?
I suppose pilots of 5, 10 ... 20 or more years know little more than was required to pass their original test?
Oh well, I suppose trying to put my ameteurish case on a forum filled with professionals was always likely to draw few friends
SS