Another "I was disappointed with 'Dead Man's Chest' too" here. (And another "What do you mean, Barbossa was on the poster?")
Speaking of the writers' commentary, I note that on the first film Elliot & Rosso were brought in after two other writers had already had a crack at it, when there was already a general outline and a set of characters for them to work with; on the second film, they were the first and only writers, meaning they had to create the whole thing from scratch. I don't say that this is significant, but I wonder if it might be.