TopHat 25 Mk2 said..
Exterior colours will be such as suits what the rest of the local moored fleet is wearing.
I've sometimes wondered what would happen if an immaculate varnished Metre Boat like this;

or a beautiful blue Swan like this;

was moored amongst a bunch of scruffy, rusty white boats like this;

If someone complained to the RMS that the Swan or varnished yacht's exterior colour did not match the rest of the boats moored in the area, would the RMS force owner of the Swan or Metre boat to pay someone to paint their yacht dirty white with rust marks, to match the other boats moored nearby?

What the hell do they mean by the rule anyway? Does it mean you can't moor an immaculate black boat near white ones? Does it mean you can't moor a purple boat near a green one because the colours will clash? Yes, I can understand why they don't want wrecks sitting on buoys, but a rule as stupid as this one should never have been written.
Hmmmmm....I just realised that a boat with "MARITIME" or "POLICE" written down the side in big letters would not suit many mooring areas because it does not match the usual colour scheme of moored yacht. Who should I complain to?