Dozy,
In the right hands and without all the "protections," your genteel A320 could be made to do a low g airshow on the order of what Bob Hoover did with his Aero Commander.
To make it fly in the genteel mode, they have provided some safety margin from the performance boundaries. What people are not talking about is how big the safety margins are (that is closely held data because in the wrong legal hands, it could be said that AI took away a pilot's maneuvering margins and thus caused an accident.
But I'll bet that there was .02 g available from the airframe that the computers were not letting the pilot obtain in the Habsheim accident.
Surely you must recognize the need for some safety margin from an engineering standpoint. There is variability between aircraft after all. Surface contamination of the wings does happen.
What a properly trained pilot can do is to operate an aircraft right up to the boundaries and if the boundaries are slightly exceeded, he will maintain control and correct back toward the actual boundary. (Unless an intervening computer limits this performance.
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