How much is a "tiny pinch?" I'd give it a shot just to see how it tastes. Couldn't be any worse than milk, sugar, lemon, or honey, etc. Those additives completely kill any tea taste--which I really like--at least for my palate.
While we can frown upon people using microwaves for making tea, or adding salt, or something other than the traditional way. It has to be said that I have had plenty of awful cups of tea made for me in this country.
Cheap teabags, skimmed milk, and my real bugbear, too much milk.
I prefer to make my own tea. That way its done properly.
I find most things simply do not stay very hot for very long when heated up in a microwave. I use it for popcorn, reheating pizza, some defrosting and such. Just never been a fan of the micro-wave. I'll not eat in restaurant I've I hear a micro-wave dinging.
Salt in tea simply sounds wrong. But, different strokes I suppose.