The effect of mechanical vibration (jitter) is an increasingly important parameter for next-generation, long-distance wireless communication links and the channel models used for their engineering. Existing investigations of jitter effects on the terahertz (THz) backhaul channel are theoretical and derived primarily from free space optical models. These lack an empirical and validated treatment of the true statistical nature of antenna motion. We present novel experimental data which reveals that the statistical nature of mechanical jitter in 6G links is more complex than previously assumed. An unexpected multimodal distribution is discovered, which cannot be fit with the commonly cited model. These results compel the refinement of THz channel models under jitter and the resulting system performance metrics.