Is that pinch of salt necessary?

I don't think it is necessary at all.

Salt is one of those things people get used to and think they can't do without but most of us used to take sugar in our tea and coffee but then gave it up and don't miss it. Salt is just the same.

We get enough salt in our diet from things like bread and cereal and it definitely is a bad idea if you have high blood pressure. My DH does and if he drinks Horlicks it goes up. There is loads of salt in Horlicks!

which it, not is...

I used to wonder the same thing happytrish, so I experimented. In some cases, the result is better with salt and some cases it doesn't seem to make a difference to the taste. I think it depends what other ingredients are used. A rich fruit cake with spices added shouldn't need salt, and if you use salted butter in a sponge cake, that won't either. I wonder now if many early cake recipes used "sweet" (i.e. unsalted) butter and that's why they added some salt as a flavour enhancer, which is most certainly is.

I havent cooked with salt for over thirty years (hypertension) and apart from one or two guests who put salt over everything no-one has ever mentioned it.

My understanding is that it enhances the flavour. I do like chocolate cake that has a slight hint of salt. I wonder if it has evolved from the USA? We came across quite a lot of sweet things that had salt added like fudge, 'taffy' and salted caramel when I was in California.