I have not researched this but somewhere in the back of my mind I recall the word angling is derived from “Fishing with and Angle”
This goes back to pre history when “hooks” or as they were known “Angles” were made from bone. Obviously a bone with a built in angle. 🙂
I suppose if you took a bone something like a wishbone and with a lot of patience and a sharp flint you could fashion something like a hook. Some sinews from the leg of a deer, a worm from the midden and away you go.
Personally I think a Kamasan B170 and some fluorocarbon is the way to go 🙂
However angles can very important when fishing.
The angle of the rod in the casting stroke will determine the shape of your Loops.
Too much and you will lose distance. Too little and you risk tangling up a multiple fly rig.
When using a sinking line you need to maintain an angle with the rod tip and flyline to keep in touch with your flies and this angle influences how your flies come up to the “hang.”
Casting angles relative to the Bank or Boat determine where your flies are fishing and particularly with multiple dry flies or the washing line will increase or decrease the chance of a fish seeing them.
In a drifting boat your presentation angle may need to vary with the strength of the wind.
The use of a drogue can also change these dynamics.
Your position in the boat and how you are sitting can affect your natural casting angles as can whether you are left or right handed.
So perhaps things are not as straight forward as they seem.
If they were we wouldn’t need the angle and perhaps we wouldn’t be angling. 🙂