the whole time traveling thing. the people on the island we have seen so far who traveled have all spent time on a certin part of the island, the beach. julliet swyer, gin, farrady miles. at least one of the suvivours of 815 can't remember her name the hostess was with the others, talking to john locke when they moved out of camp before the island moved, locke after a load of adventures was with this group when the island moved and traveled through time but apparently she didn't.
desmond spent the most time on that part of the island (not on the beach but only 15 min walk away) and his time travel 'condition' is acute.
in the first and second season we saw the others draw a line of demarcation on the island and also 'kidnapping people' for there 'own good'.
the original 'hatch' had quarinteen markers around it
the people who went back to the island includeing ben all spent time on the beach.
could what ever happened that made the hatch nececessary, could one of the consequences be that it infects people on that part of the island and make them prone or extra scencitive to the whole time travel thing.
just a suggestion or a obsorvation on similarities that might not mean anything.