This research responses to major challenges in the development and commissioning of multi-robot systems. A mechanical coupling through a handled workpiece may result in damage to the piece or the entire system when the distance between the robot TCPs deviates during motion. This paper introduces a novel method that allows to successively test and characterise a newly developed multi-robot control systems. It identifies the impact of control errors and geometrical deviations using a hardware-in-the-loop (HiL) setup in one, and a real robot system in another step. For this purpose, the distance between the TCPs is measured during HiL- and corresponding demonstrator experiments. Thereby, the method provides a foundation for a novel multi-stage characterisation process. This enables conclusions about the causes of errors in control programming, model quality, and geometric deviations.