According to the documentation,  to have Switchlincs to act as a multi-way switch, one only needs to create a scene with the the required Switchlincs all configured as controllers. Sure, it works but, I don't understand why without needing responders. Can someone explain how this works so that I can better integrate various devices. 

When devices are together as controllers they are also responders so you don't need separate scenes for it

Understand, too, that this concept (controllers being responders, by definition) is unique to the ISY.  In a pure insteon sense, one would have to create multiple scenes (or links) to define multiple controller/responder relationships.