  The aforementioned Rings that show past, present, and Future uses T'A'R (as demonstrated by its interaction with Egwene's Ring) for all three presentations.  Egwene's Twisted Ring puts a sleeper into T'A'R but never put anyone into a Mirror World or forces an imbalanced link with anyone.  that's your opinion, not proven at all. the way back comes but once - you either step through a gateway or you stay. Forever. 