Lost in Coincidence

One followup to my previous "Lost" post (I can tell you're all sick of me talking about this week's episode, judging by the voluminous comments /:) )....

Let's assume the Others knew nothing about the Losties before their plane crashed. Mikhail worked with unknown outside sources to gather files on all the passengers and crew (?) only after the plane hit their airspace. Presumably these outside sources have a lot of influence to find out such things as Sawyer killed in the man in Sydney.

I hypothesised that since the fake plane wreckage had to be placed in the trench very soon after the real Flight 815 was reported missing, those who placed it probably had to have either had a hand in their crash or at least known beforehand that it was going to happen. Does that mean they influenced the inclusion of or actually chose the people who were going to be passengers on that flight?

If not, then how to explain the coincidence of so many cross-connections between the passengers, especially the ones featured on the actual show? Locke's father is the original Sawyer. Jack had to choose between his future wife and Boone and Shannon's father to save in the emergency room. Hurley and Libby were in the asylum at the same time. Desmond ran into Charlie once when he was a street musician. Sayid's American soldier handler was Kate's stepfather. And the list goes on and on: Anna Lucia was hired as a bodyguard to Jack's father. The mother of Sawyer's child once helped out Kate when she was on the run. Locke once inspected a house for Sayid's former lover. Libby met up with Desmond and gave him his sailboat. Mr. Eko visited Claire's psychic. And of course, Claire and Jack are actually step-siblings.

So how to explain so many coincidences? Were they all manufactered? Implanted memories? Part of some greater purpose to guide each of them both to Australia and to that particular flight back to L.A.?

Somewhere, somehow this questions has to be answered for any of the overarching series to make sense. The flashbacks have been so integral to the show as to almost define it stylisticly that to ultimately chalk up the coincidences to just that, coincidence, would be to hugely undermine the credibility of all the writers have produced...