More like Fe**kn yotties and yobs.
I have a large full size one off a ship that was half the length of the old RIB and I still had idiots coming across to ask what it meant, despite trying to head them off with the RIB.
A considerable number of boating folk would not know what an A flag meant or steer to avoid it unless you beat them over the head with the pole it was mounted on.
Don't get me started on A flags, you wouldn't like me taking about A flags...........