There is so much I want to know about Jefferson. But I think if a guy is stuck in a house with nothing but telescopes to watch the comings and goings then he is pretty familiar wh=ith everyone and there routines. He had to notice when the very first stranger entered the town, and when the clock started ticking. He had plenty of time to watch and see that things started changing when Emma showed up. Clearly he has knowledge of magic and knows when it is changed it is because of some other type of power or magic. Questions I would like answered are:
What is his relationship to the queen?
How did he get that hat and all that knowledge about it…maybe him and the Queen went to hogwarts together… 😛
Also why did he make a map of the area in and around Storeybrooke? Was he looking for a way out maybe? He said all of the worlds pressed up against eachother, maybe he was looking for another way to get home other than the hat.