In the beginning we see Jack waking up...hearing Hurley's calls for help, jumping into the water to save him--and then rushing over to Kate.
Later in the episode...we see the same scene play out again--but it doesn't happen the same. Did anyone else catch that? The diologue is different. I suggest you go back and watch it again if you didn't catch it the first time around.
I'm watching it again right now--so I'll type it out for you guys.
First Time:
Hurley: "Help, anyone! *other calls for help*Jack, help!"
(Jack runs through jungle, jumps off cliff into water)
Jack: "It's okay, it's okay....you can stand."
Hurley: "Oh--Oh my god, it really happened."
(Camera pans to Kate lying on the rocks.)
Jack: "Kate. (Jack swims over to her) Kate, Kate can you hear me?"
(Kate opens her eyes)
Kate: "Jack?"
Jack: "Are you okay?"
Kate: "Are we?"
Jack: "Yeah. We're back."
Kate: "What happened?"
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Second time:
Hurley: "Help! Anyone, help!"
(The scene cuts to Jack jumping into the water)
Hurley: "Oh---"
(Camera pans to Kate lying on the rocks.)
Jack: "Kate. (swims over to her) Kate?"
(Kate opens her eyes)
Kate: "What happened?"
Jack: "Can you get up?"
...conversation continues as we see the rest of the scene.
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Now, before some of you say--"The scene was just cut down to save time, and as not to repeat everything we saw at the beginning of the episode".....
I ask you.....
Watch again...watch the scene at the beginning, and the one toward the end a couple of times.
I do realize that it is cut down. We don't see Jack running through the jungle the second time. I would explain more about where to pay attention--but you all are smart; I don't think I need to do that!

Anyway, let me know what you think!!!