Great post and a good read, lots of valuable information (We get that sometimes around here).
Thanks for the link sidiag.
I plan on printing it.
Kind of a funny story to signaling.
In my area (Chicago) we have a lot of tour boats and water taxis.
These captains use the VHF for their signals. Monitoring the radio you will hear, "Passing on one." or " Pssing on two." or else you will hear, "Captain do you want One or Two.?"
I asked one of them one day what they were always talking about and she explained it was their horn signals.