In fly fishing, the principle is how you describe. The leader is nice and thin, less visible, then you have the weighty very visible line you throw with. The backing is never seen by the fish.
I guess different fish have a different perception of danger or similar.
I find it very important that the hook is more or less totally hidden when Ifish in rivers and lakes.
In the sea, it does not matter, the hook is very, very visible.
I only use bait for Hallibut and flatfish, and the hooks are visible.
For Hallibut even the tip is exposed ( I use circle hooks there)
Lots of people see fishing as an art. In our case, it is luck.
We just came back to check our 7 crab boxes. One crab and one flounder.
For a survival fishing kit - S/s hooks, strong line. Absolutely.
When I served, many times we had to get food from nature.
We fished using explosives. About 50grams of plastic.
Reindeer were taken using mil full metal jackets, I used Remingtons Armour piercing .357 mag.
Survival or getting needed food = no laws apply.
I would NOT use the fishing line in the survival kit for anything else.
If it comes to the worst you want a full strength line.
Also, what I think many bushcrafters do wrong is this: hooks are way to big. If you stand on the shore of a lake (or sea) your target fish are tiny.
You can not cast out any great distances.
So you need a tiny hook.
To get the longest casting you need a streamlined float, not one of these classis pear shaped white and red jobbies.
In Sweden we use something called a ‘dubb’, it is a plastic float with inbuilt weights. Longer casting with a rod or by hand.
Not sure the english name.
Plus, the most important: practice, practice, practice!
Practice casting, practice baiting, practice finding bait. Practice cleaning the fish, practice cooking it.
Learn where the fish stand, learn eating habits.
Here in the Lofoten we see tourists renting (bloody expensive, 1000NOK daily) boats. Then fishing in the wrong places, using wrong equipment ( usually too light)
Usually they get nothing. If they catch a decent fish that is ethical to harvest, the rod tip breaks.
Seen it many times! I made the same misstake the first trip up here.