{TAIL ~ a first wearable display} and a second wearable display of the plurality of {HEAD ~ wearable displays}, the first wearable display having: 
{ TAIL ~ a first wearable display } and a second wearable display of the plurality of { HEAD ~ wearable displays } , the first wearable display having :
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH