Disclosed herein are systems and methods for improving the performance of a fluid jet cutting system by testing and adjusting characteristics of the system based on the effect of the characteristics on forces imparted by the system to a workpiece being cut. Also disclosed are systems and methods for monitoring and validating the performance of fluid jet cutting systems, and for diagnosing such systems. In some cases, the technologies described herein can be used to determine whether components of a fluid jet system require maintenance, or that characteristics of the system require adjustment.