The first thing that springs widly to Jack head at Norrington's words is that he knows why Jack wants to head back to the Navy, to Port Royal and all its dangerous trappings. That Norrington somehow knows even when Jack doesn't and that makes him want to hatch a plan that will get Norrington to reveal the reasoning to him. But that is only a fleeting, immediate thought, before the rest of the scene sinks into Jack's mind.

The way Norrington said the words. The fact that his hand is now covering Jack's on the compass. The way he is looking at him. There is nothing there that speaks to haughty contemption and power plays, but a predatory guise there. A flirtatious one. And that somehow calms Jack. Makes the confusion and panic fade away some. There are better things to consider than why his compass is showing him three conflicting points instead of two.

Jack smiles softly. "Did you now? And do you propose to do anything about this thinking or are such thoughts not worth the effort to be put into action?"

It's quite easy to fall back into the pattern of flirting with Norrington. Reassuring, almost, by how second nature it's become in such a short time.