Thank you, Nigel, for that interesting information. I've read truly great fighters, at least up to the introduction of artificial "feel" and computer-assisted flight control input, were inherently unstable to a certain degree as that indicated a quicker response to control input. It would make sense also that a good trainer should have the same characteristics - you would have to seriously "fly" the airplane, and therefore learn it rather than be a passenger. Now and then I suppose something like an AT-9 came along that took that theory to its limit.
I should thank you as well for the interesting and quite beautiful photos of Greece, I can see why you are so attached to it.