Peteghem et al.  considered resource-constrained project scheduling problem (RCPSP) with preemptive activities. However, some points should be made clear. How and when an activity is divided? How many parts an activity should be splitted? Whether the preemptive-based scenario is correctly performed to further improve the total makespan of a project? The first two questions are not very clearly presented. As for the last question, the answer is “no exactly” after careful examination..