Hm, I didn't recall he had been chained. I really must've faded out at that part :) I suppose he could've gotten free somehow. Although if he was dumped overboard in deep water, moonlight wouldn't get to the ocean floor, so he'd be in human form. They didn't say whether the pirates could do those things in human form, but I suppose they could.

This whole thing could really suck for Jack. During his lifetime, there's always the chance someone could mess with the treasure, which doesn't seem fair.

Maybe we're not supposed to examine this curse too closely.

I think you've hit the nail on the head, there :)

I got the feeling Jack and old Bill were close. He did say he was one of the few who knew Bootstrap as William Turner, so we can probably assume they were somewhat intimate. Buddies. I find this intriguing :)