Magic does fit into that catagory. However, Magic is a blend. Magic is regular rock salt, that is sprayed with a mixture of liquid Magnesium Chloride, and an "agricultural" byproduct. Together, they work well. Alone, they don't work as well. I guess it's a good recipie, but if you leave out ingriedients, then it doesn't perform as well.
On that same note, I just applied some Magic the other day to a job here. I went back today, and the area treated is black and wet. It is snowing, and we are expected to get 1 - 3". The parking lot was treated with plain rock salt the same day the magic was applied to the walks. Where the magic was spread onto the edges of the lot near the walks, snow is not building up. The rest of the lot is covered already. This is my first experience with Magic, and I am impressed with the results.