-a ) check out Leo Marks' "Between Silk and Cyanide", which touches on a telegrapher's signature 'fist' - they were distinguishing between different (German) senders of coded messages over the air.
-b) this is still relevant today for (especially amateur radio) morse code operators
There was an Apple Mac (sub-) team visit to Inmos in the UK, hosted by Ian Barron, sometime circa 1982 - 1983. Bob Belleville, the Mac team's director of engineering, led the trip. I remember Ian had a Jaguar with twin fuel tanks, but told the story of how he forgot to refill the first one when it was empty, so sometime he totally ran out of fuel. JG (John Giannandrea), later of Netscape, was at Inmos around then. (He was at Apple last time I checked.)
Someone else posted here on HN in the last year or so; she lived in the Pacific NW and had built a database-based - web site that lets one enter constraints and find hints that help answer your question. Alas, I can't find the link at the moment.
I have been calling this "Haeberli's corollary" to the Third Law of Thermodynamics - "globally, competence is not conserved" - it's leaking out of the universe, somehow...