LOL. I agree with your faultless description. In my original post I was lax in my approach to the original advice given, not wishing to offend the poster of this onerous advice.....2. Carry a couple of cheap air horns and don't be afraid to use them. 5 short blasts means "I am in trouble." You don't have to be sinking, burning etc. to warn that BFS that you don't have things under control.
OK you want to go all sea lawyer on me. "Five to stay alive" will be understood by most (but not all) other (commercial) vessels underway. Recreational, well, I watched a guy set off SOLAS parachute flares to celebrate the Forth of July. He didn't understand why about 15 vessels in the north end of Lake Michigan began reporting a Mayday.
Note that the rule states "or is in doubt whether sufficient action is being taken by the other to avoid collision," I humbly suggest that when a BFS (big frigging ship) is bearing down on me because he doesn't understand that I am "not under command" (since in the case in point our author felt that he could not get out of the way in time) he would rather I gave him 5 then hit me. As I said before - the paperwork is a bitch. (Rule 3 - definitions - not under command: The term "vessel not under command" means a vessel which through some exceptional circumstance is unable to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel.)
Note also that rule 2 says:
(a) Nothing in these Rules shall exonerate any vessel, or the owner, master or crew thereof, from the consequences of any neglect to comply with these Rules or of the neglect of any precaution
which may be required by the ordinary practice of seamen, or by the special circumstances of the case
(b) In construing and complying with these rules due regard shall be had to all dangers of navigation and collision and to any special circumstances, including the limitations of the vessels involved
, which may make a departure from these rules necessary to avoid immediate danger.
So perhaps you are correct that "5 to stay alive" is not technically correct. But just as I doubt anyone would give you grief for saying MAYDAY when you could have used PAN I doubt the master of a BFS would complain if you gave him 5 to avoid a collision. Of course you could argue it out in Admiralty Court if you survive the collision.
Fair winds and following seas.
PS I think you meant "erroneous" rather than "onerous."