A few years ago there was an article in the British Journal of Photography about adding anhydrous (?) sodium suilphite to rodinal to produce a finer grained negative. I remember thinking how impressive the images were but now cannot find the article or remember how much sodium sulphite should be added (I believe it was 5 grammes but cannot be sure).

Has anyone heard of, or better still, tried this method and are the results worth the effort?