"And in the film The Dutchman and The Pearl are separated by a ginormous whirlpool. How the fuck are they able to just suddenly move to and from both ships???"

In the movie, the various characters were able to move back and forth either by swinging on ropes or because the ships were so tilted, they crashed into each other over the whirlpool, if I recall. ^^; Neither way was clean and easy though, so I really can't see how Kate failed to notice she did it.