I think most of us are on board with the idea of Syrio being a FM, and that he is still alive. It makes perfect sense that he and Jaqan are the same person. After all, the first time we hear anything about Jaqan is shortly after Syrio is left fighting off some Lannister clowns and vanishes into thin air. No one seems to know who Arya's dancing master is....how was he recruited for the task in the first place? Could be a fellow FM in KL....gee I wonder who
....called him forth for the task, with the expectation that at some point he would send young Arya to the HoB&W. So when Ned was taken into custody and Arya went on the run, with Yoren sneaking her out of the city, the only way for her recruiter to stay with her was to follow her in the same party. Enter, Stage Right: Jaqan, a strange prisoner who speaks in third person with a penchant for riddles, not unlike a certain dancing master.
This of course begs the question of whether or not the "Master Plan" has always been for Arya to make her way to the HoB&W, and if so.....whose the master planner?
Because it obviously wasn't Ned.
If Varys is a true FM, this could only be his plan. I must then ask why would Varys care about Arya becoming a super assassin?
Unless he intends to use her to carry out a certain task?
The possibilities are intriguing!