Dyneema is surprisingly tough, remember it is designed to be dragged over rocks etc in off road winching. What happens is that you get a furry layer on the outside which sort of protects the core of the rope, without apparently losing much strength. Its only real weakness is cutting over a sharp edge under tension. Having said that if my winch drum looked like the rusty one I'd bin it on the grounds of structural strength! They aren't that expensive and if I wasn't getting a new trailer then I'd be thinking about retiring my current one after 4 seasons of use.
A Boat is a hole in the water, surrounded by fibreglass, into which you throw money...
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