Energetic disorder plays a central role in many of the theories of charge transport in molecularly doped polymers, MDP. This assumption can be tested experimentally. A review of experimentally characterized MDP systems reveals that there is almost no experimental evidence to support the prediction that the experimentally observed activation energy is due to energetic disorder. Instead, the data appear to suggest that the activation energy is primarily intramolecular in origin.
L.B. Schein, Andrey Tyutnev, "The Source of the Charge Transport Activation Energy in Molecularly Doped Polymers" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP24), 2008, pp 173 - 175, https://doi.org/10.2352/ISSN.2169-4451.2008.24.1.art00046_1