... CRM? God, that was ducking the captain's fist!

I learnt to fly with a small group of chaps some years ago ... the instructor (ex Airline and now long dead) had a view that a fundamental instructional technique involved a rolled up newspaper .. the student was permitted one mistake in any given area of training, a further briefing, and then a clout around the ears with the said rolled up newspaper if the mistake were to be repeated.

Perhaps not PC in these modern days but definitely focussed the student's attention on the task at hand .... with the exception of one student (who took around 10 hours - obviously a tender headed youngster) we all went solo in 4-6 hours so perhaps there may have been some instructional validity in the technique ?