The softening process consists of recovery and recrystallization. Despite the significant effect of recovery on the softening, recovery has not enjoyed the attention as much as recrystallizaion has mostly due to difficulties in the microstructural characterization of recovery. The present study introduced GOS qualitatively and quantitatively to gauge the microstructural evolution occurring during annealing. Then the GOS analysis was applied to discern alloying effects on recrystallization in hot deformed Al-Cu-Mg alloys. Recovery seems accountable for the retardation of recrystallization in the Mn containing alloys. By adding Zr to Al-Cu-Mg-Mn, recrystallization could be further inhibited.