Bill and Bryan are Chief of Waivers and Chief of Course, respectively. Per the first paragraph of Appendix E, Section IX, their responsibilities prevent them from being the primary SSS.
Lynn, my role as chief of course is to be sure we have a course design and set up crew for each event. I try to let the designer of the course take the set up lead and often simply support the process and give comment (along with the rest of the crew) for safety and configuration issues. I don't believe the role of Course Chief should prevent me from serving as SSS at an event where I am not the principal course designer.
I throw this out here for discussion because I have always interpreted the rule to mean that the SSS cannot serve any other role during the actual event. For instance, serve as a Corner Captian, Starter, Course Control, Grid. I've always figured that the SSS can assist with set-up of equipment, layout of grid and course or what ever else was needed to get ready to run the event.