I am finally getting back to trying to rewatch Season 2 and 3. I watched all of season 1 and the first 4 episodes of season 2 a couple of months ago. anyway, tonight I was watching the other 48 Days.
Season 2 seems to be very prominent in season 5, alot of things seem to make a little more sense going back to it after seeing season three, four and the initial part of season 5. In this episode, Ana Lucia's in charge of the Tail Section Survivors and finally she realizes that Godwin isn't a part of the survivors. She asked him "Where do you think they got it?" What you ask, the army knife. They found a U.S. Army knife on one of The Others. Well after seeing Jughead we know conclusively that the U.S. Army was once on the island in the 1950s and The Others eliminated that threat to the island. While eliminating the soliders, they stole their camp and clothes as well, including their gear. Guns, knifes, etc.
I think Season 2 is a major key to season 5!