A320 - link btn Maneuvering load limits and VFE
 

In Airbus 320, Maneuvering load limit with flaps down is 0 to +2g. It means that flaps can also take extra load if required. If this is the case, how exceeding VFE causes trouble?

The point I want to make is about the stress on the surfaces. Increase in stress due to increase in load factor or Increase in stress due to airspeed beyond VFE, how they are different? stress is stress after all. A surface experiencing stress [force] doesn't change its behavior as per the source of stress.

Assuming alternate and direct law VFE max can be exceeded. It has nothing to do with LF. Don't forget damage to the slat and flap tracks can occur in an overspeed.
Boeing Douglas etc engineers design max flap speeds with a fudge factor to cover unexpected overspeed cases such as severe turb. If Airbus has such a built in factor I wouldn't know.