This is a simple question, but maybe a strange one.
Suppose that you have several Accutrons (specifically some mixture of 214s, 218s, & 219s) running at one time. Do you find that, if they are kept close together, in basically the same orientation, & in a situation which readily transmits vibrations ― for instance, dial-downward on a hard table surface ― or at least without any sound-deadening material, that they will keep closer to the same time than if they are separated? I am intrigued by the possibility that the communication of fork vibrations from one movement to another could help to hold the two in lock-step. Some preliminary observations of mine suggest that this may be so, but I only have three running Accutrons (two 219s, & one Citizen 218-equivalent), so I can't really study this topic with any thoroughness.