blankWith the dress sinking down,Elizabeth is free from the dress and whatever constraints may have come from the dress, like the restraints from the corset,you have to look at what Elizabeth is wearing, this is the key to the movies
Will is smart, he knows this is Elizabeth's dress and he now knows Elizabeth is clear of the death threat that is represented by Beckett, he knows she was the one that got the ship to go to Tortuga and she is safe from Beckett, that is a really important story moment because it does allow Will to focus to something else, and the thing he can focus on now is his vowel to his father and he has a sense that Elizabeth is capable of taking care of herself once she was clear of the situation
They confirm that Lizzie is on Jack's thoughts (someone is vexing Jack Sparrow and various lines that he delivers suggest that the someone is Miss Swann). They also confirm that Lizzie is eager for the physicality of an intimate relationship and is frustrated that she has been denied this with Will.
They discuss the compass at length. It does not point to one's heart's desire- it points to what one wants. What one wants can waver. It points to Jack for Lizzie but perhaps only briefly. On the beach the compass always points to the chest- but Lizzie mistakenly thinks it points to Jack. There is a strong suggestion that there is no ambiguity when Jack holds it (row boat scene at the end)- that it ALWAYS points to Lizzie.
The CURIOSITY conversation is just a challenge. They are both playing a game with each other. They both want each other, but only on their own terms. Lizzie is bothered that she has a physical attraction to Jack and he in turn is bothered that he wants a girl that is really not his type or someone that he wants to want.
With the KISS of death scene Lizzie gets to slake her lust and drown her guilt for feeling lust for someone other than Will but also save the man she loves (Will). We have to ask would she have been so severe on Jack if she had not been so tempted by him? When he is dead he is no longer a temptation. Also- the chain- the first time they met was about him being shackled and using her to escape from that & that is tied in to the last scene. Basically, the writers were given a chance to let Jack & Liz explore the chemistry they have and they took it.
The bit about the kiss,doesn NOT bode well at all. *sniff*