Read that the Senko worm has a salty taste made into it.   Would it be advantageous to add the salt taste to other plastics?  Seems like you could take a file brush which has hundreds of tiny metal "needles" used to clean files and just press the worm in just enough to penetrate the surface and then pack the worms in a baggie with some salt water and let it penetrate the openings made in the worm.  If the salt is on the surface, it will just dilute when the bait hits the water.

Worth  doing it or not?

No.

The salt will dissolve almost immediately when the bait hits the water.

Salt on the outside of the bait serves no purpose at all, part of it flies away from the bait when you cast, another part dissapears the moment it touches the water, the rest dissolves as the bait sinks so by the time it reaches the bottom you got yourself an unsalted bait.

Salt dissolved and cooked in the plastic not only adds salt flavor but also adds weight to the bait which also determines the sink rate of the bait.

salt is made into those lures, putting salt on the outside will not work, as already mentioned it will dissolve when it goes into the water

Just put a mess of worms on a paper plate & liberally coated in salt and pop them in the microwave oven for a few seconds

Per liter there is 3220 milligrams of sodium (salt) in blood plasma