Duffle Coats aren't for Duffers
I remember the reassuring weight of the duffle coat I wore to school, and the red tartan lining that welcomed you in. It was incredibly warm, particularly worn with a balaclava. I liked how the snow stuck to it too and the smell of the boiled wool after rainfall. Like all timeless classics the coat was fit for purpose and duffle coats have required little alteration since the British Royal Navy issues up to World War 2. Incidentally, neither has the balaclava, but no-one seems prepared to wear or produce them nowadays. Maybe I'm soft, but I like to wrap-up well in winter.
Midships in a force nine galeWith the original navy duffles hard to track down, there are modern options out there. Burberry have a nice example this season. I'm not sure about a detachable hood, as I would say that was intrinsic to a duffle, or the colour black. I would need to see it up close to see if it would pass muster midships in a force nine gale. I would think not, but it would probably be fine for a stroll to the nearest pub.
More to Tweedy's taste are the Gloverall duffles. The company has an impeccable heritage for them, having first sold the Royal Navy's surplus and then produced them in its own right since 1954. In the 1960s they became fashionable and associated with the CND marchers at Aldermaston, wearing their badges and suede shoes. Since then they have a reputation that is equally eccentric and classic. Their 'Monty' in tan looks good, with wooden toggles and jute fastenings. Just need to find a balaclava now.