In hard real-time systems, gain time is defined as the difference between the worst-case execution time of a hard task and its actual processor consumption at run time. This paper presents the results of an empirical study about how the presence of a significant amount of gain time in a hard real-time system questions the advantages of using the most representative scheduling algorithms or policies for a periodic or soft tasks in fixed-priority preemptive systems. The work presented here refines and complements many other studies in this research area, in which such policies have been introduced and compared. This work has been performed by using the authorsrsquo testing framework for soft scheduling policies, which produces actual, synthetic, randomly-generated applications, executes them in an instrumented real-time operating system, and finally processes this information to obtain several statistical outcomes. The results show that, in general, the presence of a significant amount of gain time reduces the performance benefit of the scheduling policies under study when compared to serving the soft tasks in background, which is considered the theoretical worst case. In some cases, this performance benefit.