Software Fault Injection (SFI) is an established technique for assessing the robustness of a software under test by exposing it to faults in its operational environment. Depending on the complexity of this operational environment, the complexity of the software under test, and the number and type of faults, a thorough SFI assessment can entail (a) numerous experiments and (b) long experiment run times, which both contribute to a considerable execution time for the tests. In order to counteract this increase when dealing with complex systems, recent works propose to exploit parallel hardware to execute multiple experiments at the same time. While Parallel fault Injections (PAIN) yield higher experiment throughput, they are based on an implicit assumption of non-interference among the simultaneously executing experiments. In this paper we investigate the validity of this assumption and determine the trade-off between increased throughput and the accuracy of experimental results obtained from PAIN experiments.