1. There is no triangle, unless you are referring to the thing Elizabeth wanted most at one point being the chest, and at another point being Jack.
2. At no time did Jack was wibbling about Elizabeth, or vice-versa.
3. If you think Jack using Will as leverage to serve his own interests, or Will taking action against Jack to save a loved one, is a perversion of their relationship in the first movie, then that's what you think.
4. Jack was never enamored of his ship; he was and is enamored of what his ship represents: freedom. And, of course, as it turned out the very thing he wanted so much he was willing to make a deal with the devil to get, has come to represent either a hundred years of servitude (and eventual loss of identity) or death.
http://www.wordplayer.com/forums/moviesarc07/index.cgi?read=85939
OK, I'm going to use this quote from Ted to further my interpretation that it in no way matters WHAT-SO-EVER where the compass was pointing.