Amral is 270a.
Im on about 310 65 before mid etc. Im not disputing the need for them, but its should be promulgated. I train alot of ab initio f/o from cadet to jet. In the early stages you need something to hang your hat on. Trying to expalin a restriction that you cant prove is annoying.. Not a train smash just makes me hoarse, having to give heads up to unpublished stuff when planning exercises would be so much more beneficial if one could present all the info and let them figure it out. Second guessing a candidates knowledge is the worst form of demoralising technique. Bit of a tangent but my perspective.
Cheers