Plumper may disagree all he wishes. The matter was adjudicated at Admiralty. The specific rule, 34, relates to manoeuvering and warning signals and gives absolutely no reference to being made fast to the shore or ground.
Five short would be wrong, a point that the court was at some pains to make, to our dismay. The proper signals are referenced in Rule 36. As in neither case, mine or the OP, was restricted visibility a factor 'Romeo' would be incorrect as well.
The Rules of the Road make no allowances for "the folks" and we really didn't think of presenting that concept at Admiralty. Furthermore, Rule 36 instructs that the signals given be such that they cannot be mistaken for any other. Given that the court found that the alliding Master's claim that, upon hearing the danger signal, he assumed we were underway was persuasive to the court it is hard to argue that the danger signal met the requirements of Rule 36.
Lima and Uniform are not used in Rules of the Road situations because Rules of the Road situations deal with vessel's underway, under the steering and sailing portions. There is no prescribed signalling for a vessel at anchor other than lights, shapes, and sound signals in restricted visibility. The only applicable rule is 36 which dictates 'signals to attract attention'.
I started the other post to highlight that there is ignorance of signalling. Indeed, three professional mariners with years of sea time-two holding Master's licenses, made the same mistake Plumper now makes. If he chooses to argue in favor of ignorance, regarding the Rules or signals to attract attention, there is little that I can do in responce.
I may have made the incorrect assumption that when the OP said, "we stopped to have lunch" that he meant they anchored.
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