Oh dear!
A wholesale misunderstanding of both large aircraft and swept surface aerodynamics.
Sudden control deflections particularly if violently checked could overstress the fin. That is true of virtually any design with a swept fin due to its ability to create large angles of attack. Add to that a flight regime which is at the upper end of the speed range for full (i.e. unlimited) rudder travel and you have a recipe for overstressing the fin.
Just take a moment (no pun intended) to think about the amount of force that the fin would have to generate to produce the rates of yaw and controllability to acheive certification for a 100+ ton airliner. Then consider that the surface is attached only at one end and must deal with non-linear forces through twisted axis thru a speed range of 70 to 400 knots IAS and MNs up to .85+. Now tell me how you would help to protect the surface from overly agressive control inputs?
I'll tell you how: A Fly By Wire protected envelope. The A300 is not a FBW aircraft and the A320 only has conventional rudder limiters with a very fancy yaw damper. One day, with development and engineering aircraft will become far more difficult to break.
Fin separation at very high sideslip angles is not new (e.g. Convair B-58) and therefore we should not be surprised if it occurs. Advanced Manouevre Programmes in the 'wake' of some 737 accidents taught pilots more aggressive control inputs including use of rudder to improve roll rates. However well intentioned that this was it seems that the dangers of imprudent rudder application were not highlighted enough.
Conclusion: Unusual attitudes / jet upsets, use aileron/spoiler up to its full authority then carefully augment with rudder.