I don't believe I said 'useless.' Some who were granted amnesty and returned had their sons serve in the Grande Armee, such as Soultrait and Lathounnaye (both of whom left letters and or memoirs which are valuable). The ones I'm referring to generally speaking are those that followed Louis home in 1814 and demanded their privileges back no matter who was either done out of a job or position or were persecuted by the royalists.
Louis refusing to stop the royalist nonsense, which included the White Terror, and that only made him less popular and led to the further nonsense under Charles X.