Why a bow thruster is useful in the Bay of Biscay.

[Stemar]

the suggestion that it's a good idea to put some effort into seeing what's already broken before setting off into the Atlantic

I very much doubt if there's anyone here, least of all an experienced delivery skipper who would argue that, but sometimes it just isn't practicable, so you do your risk assessment and go or don't go. Wibbling around doing tests and overstaying a legal welcome is likely to have consequences that are harder/more expensicve to deal with then a minor incident en voyage