LIGHTS & SHAPES
There is little to say about lights. The Rules are clear, and there is no excuse for not showing the right ones at the right time. You have a choice when sailing of the tricolour at the masthead (saves electricity) or bow and stern lights. Just don’t show the tricolour, bow lights, stern light and steaming light all at the same time!
As for shapes, most of us only carry two: an anchor ball and a motoring cone. The first should be hoisted whenever you are at anchor. It is not difficult, and Rule 30 tells us to.
The motoring cone is, in my view, generally a waste of time, and hoisting it can be a hazardous evolution. If my wife and I are motor-sailing in a lumpy sea, I really can’t justify either of us making a trip to the foredeck to hoist a shape which indicates the obvious. If motoring with the genoa set, it won’t be seen to leeward anyhow.
Some harbour authorities stress the importance of showing a cone, but I am prepared to take the risk. Whether you accept this argument is entirely up to you.
However, one sailing area I have faithfully hoisted my cone is the inland waters of the Netherlands. The Dutch take it seriously, and I’m not prepared to cross them.
CONCLUSION
As I said at the start, the Colregs are generally very clear and unambiguous. In my seagoing days in the Royal Navy, as a bridge watchkeeper, navigating officer and commanding officer, I was punctilious about ensuring that the Rules were followed unerringly. As a yachtsman, I opt for some intelligent interpretation.
Nevertheless, the Rules are mandatory, and any divergence from them which could be shown to have contributed to an incident would require justification at an enquiry. If all else fails, Rule 2 may be your saviour.