I would point out that molecular dynamics simulations are known to be inaccurate, and that by choosing the atomic force fields you can get essentially any result you want. For most materials simulations, these parameters are tuned to some experimentally realized system. It is not obvious to me that such tuning is being done in the case of these molecular gear assemblies, and even less obvious to me what would constitute an appropriate system to tune towards.
I would point out that molecular dynamics simulations are known to be inaccurate, and that by choosing the atomic force fields you can get essentially any result you want. For most materials simulations, these parameters are tuned to some experimentally realized system. It is not obvious to me that such tuning is being done in the case of these molecular gear assemblies, and even less obvious to me what would constitute an appropriate system to tune towards.