I think synchronicity is a form of personal observation,
which has it's roots in the collective unconscious of all living beings.
We don't always see what's in front of us, but that doesn't mean it's not there.
Take Stephen Wiltshire's drawing ability as an allegory of sync.
He goes to a foreign city like my home town Brisbane, Australia,
takes one plane flight over the city and then draws it in accurate detail from memory over a couple of days.
I have lived here all my life and not seen what he has seen about the city I live in, not because it wasn't there, only because it never got my attention.
To me sync is like a boat trip down the river, if I relax and just observe the scenery with no fixed point in mind, then I'll see what I have to see and someone else on the boat will see what they have to see and sometimes we'll see the same thing and put our observations together to enlighten the both of us a little better on what we just saw, which may end up changing both our lives for the better on that point.
If on the other hand I set off down the river determined to observe only what interests me personally, and the other person on the boat says did you see that?
I might have missed an opportunity to enrich my life because I was not interested in what the other guy was looking at and wouldn't even take the time to look, because my mind is focused on looking elsewhere for something specific.
To me sync works because I let my unconscious be my guide, because it is a lot like a Stephen Wiltshire, it notices everything around me, whereas I just see what interests me when operating from my conscious part of the brain only.
So it's not like a "go with the flow", it's more go with what comes up from the depths of my being, or my "All Seeing Eye"
(Stephen Wiltshire), because it sees things that I don't notice and is in a much better position to guide me than my blind ego.
We are all on different walks in the same part of the forest, which is why I like hiking, because you can never do the same walk twice and there is always something else to discover if you keep your mind and eyes wide open.
My own personal take on synchronicity is similar to Jung in that my consciousness is part of my vast unconscious which is part of the universal collective unconsciousness (or God mind), so to me, we all have access to the same source, because we are the same source