>>"let's face it in real dangerous situation few weeks or even months are not enough to act appropriately."<<
True... even people who have trained for years freeze up... when confronted with a real scenario.
If one has never faced a life and death situation during their lifetime, I do not care how well they are trained... they never really know how they will react until the time comes. Others may react, but all their training goes out the window because they have never developed the necessary instinctual movement or proper muscle memory skills... this is usually, but not always, from not practicing (properly) enough.