I think that is the whole trick - they look like they are all in parallel on four wires, but really two of the wires are daisy chained through each device (like

I think that is the whole trick - they look like they are all in parallel on four wires, but really two of the wires are daisy chained through each device (like serial LEDs). In this configuration you can do the light tricks without knowing the order, but you can also enumerate the order. I have seen addressing based on hop counting, or by appending your ID to "who are you" message. Eg: Host sends "who are you" first device appends an ID number and then propagates the message forward in the chain. Each device does the same, until the last device in the chain (which detects electrically or via a timeout that there are no more devices) decides to loop the message back to the host.