I don't use cast iron for boiling, simmering, and otherwise cooking liquids. It's a frying pan for frying.
I use stainless steel sauce pans, pots, etc. for liquids.
I clean the cast iron while it is hot. A lot of food comes off without water, only a little water is required to remove the rest, and the cast iron is mostly self drying. Since I usually use electric burners, I can stick it back on its burner to dry with the burner's residual heat. [1] This is also a reasonable time to oil it.
If something is really stuck, for example if I didn't clean the pan when hot, I heat the pan again and clean it when hot.
Cleaning stainless steel when it is hot is another algorithm that works on my machine.
There's certainly ritual and habit around my use of cast iron but I am not saying you should use cast iron. Particularly since I enjoy the process of using cast iron and you don't.
[1]: on my portable butane stove, I will reignite the flame and reheat the pan if necessary.
Our most used cast iron skillet had a tenacious crust of burned-on grease and carbon that had collected over the years, and because the surface of the bottom of the pan was no longer smooth, many foods would stick. Initially I thought the unevenness was the result of corrosion, but no. I took a sturdy stainless steel spatula to it and with quite a bit of elbow grease over a few days managed to scrape off all the crust and get down to the smooth surface underneath. Now anytime anything sticks and the surface isn't perfectly smooth, I use the spatula with a little water and Dawn dishwashing liquid and quickly scrape until it's smooth again (it's easy to feel with the spatula), followed by my normal routine anytime we use the pan: drying the pan with a dishcloth and then by heating it on the stove, wiping the surface with a few drops of olive oil, and leaving the pan on low heat for a few minutes before hanging it back up on the pot rack. Works great!
Maybe GP's mention of "boiling salt" does not refer to "table salt" but salt in the more general chemical sense. Perhaps they use Ethylammonium nitrate with a boiling point of 240 C (464 F).
Any food on a cast iron pan is converted to carbon ash by holding the pan at 750F for a few tens of minutes if you have a functional exhaust fan. This is useful for the most extremely stuck stuff like large amounts of meat mixed with blood. No amount of scraping would get that off. However the ash came off effortlessly. The electric range was old and worn out but got the job done easily.
I found a hoard of old unused sad cast iron pans at my wife’s grandma’s place. Putting them in the electric oven and running a self-clean cycle completely stripped them down to bare metal. From there, they were seasoned from scratch and have been in service for a decade now.
I don't use cast iron for boiling, simmering, and otherwise cooking liquids. It's a frying pan for frying.
I use stainless steel sauce pans, pots, etc. for liquids.
I clean the cast iron while it is hot. A lot of food comes off without water, only a little water is required to remove the rest, and the cast iron is mostly self drying. Since I usually use electric burners, I can stick it back on its burner to dry with the burner's residual heat. [1] This is also a reasonable time to oil it.
If something is really stuck, for example if I didn't clean the pan when hot, I heat the pan again and clean it when hot.
Cleaning stainless steel when it is hot is another algorithm that works on my machine.
There's certainly ritual and habit around my use of cast iron but I am not saying you should use cast iron. Particularly since I enjoy the process of using cast iron and you don't.
[1]: on my portable butane stove, I will reignite the flame and reheat the pan if necessary.