I would like to talk if you are interested. I have SD - have had it for 4 years. I am avoiding botox treatment, and am trying to come up with a remedy/cure on my own.
I don't believe it is a neurological condition as much as a physiological system breakdown that leads to a neurological response that generates muscle spasms and tension. I have a bunch of ideas on points of failure and possible hypotheses for how the system is operating. I am not a Biomechanical engineer however. I do have a close, intimate perspective on what the condition feels like however as I have lived with it for a while. I have even been able to create my own work-arounds.
I have been trying to find people who are interested in troubleshooting the oral-nasal-palatal-pharyngeal systems to identify the failure point(s) and (hopefully) develop a fix.