The strategy for an east to west transit of the Northwest Passage

Whereas in the former cases, the success of a voyage depends primarily on the experience of the skipper and crew, as well as the suitability of the vessel, in other words, on objective criteria, in the case of the Northwest Passage, there are several subjective criteria which are entirely out of your control and therefore can result in failure unless you are prepared to do all in your power to minimize those risks.