I had an idea a couple of weeks ago to go back and re-watch Season 5 (for the third time). This time I wanted to watch each episode while asking myself the question, "How does this episode help to close out the series?". I was thinking that perhaps this could help me find some clues as to how the show might end.
I know we are very, very close to the beginning of the end with season 6 starting in only 4 days but here is what I have found so far.
S5x1-"Because You Left":
This episode introduced us to time travel which was needed to get everyone to the time of The Incident.
It also introduced the LOST "rules" of time travel ie, whatever happened, happened. This is an important clue as to whether Jack changed anything in the Season 5 finale. Personally, I don't think he did or at least I hope he didn't.
This is also the episode where we see Richard tell Locke that he has to die. Since this advice really came from "Bad Locke" and Richard was only the messenger, I wonder if perhaps this was the "loophole". Everything that Locke does from that point on was done based on instructions from "Bad Locke".
This episode explained why the Oceanic 6 lied. It also explains some of the Oceanic 6's motivation for going back to the Island. Other than that, I really couldn't find any good clues.
On a side note, who was in Anna Lucia's body? Was it Jacob, The Man in Black, Anna Lucia, Christian Shepard, the list goes on.... Whomever it was, they instructed Hurley on all the steps he needed to take (change his clothes, get Sayid somewhere safe, etc.) to get things straightened out. Except that she specifically tells Hurley don't get arrested and he does anyway!!
Stay tuned. More to come as I continue to re-watch and analyze.