Your grandmother swore by hers - but that was in the days of unsifted flour. Today, most flours are so uniformly ground - you don't need to sift for the same reason your grandmother did - you need only sift to combine white ingredients like flour, baking powder, etc. Still, a sifter is nice to have! One use is to sift icing sugar on top of warm desserts - it's a fast way to get a lovely decoration. Professional kitchens will often combine a sifter with a paper mask with their logo cut out. The result is a unique design on the finished cake.
Can any good brand of chocolate be used for dipping strawberries and still set up hard when cool? If not, can anything be done to it or added to the melted chocolate to ensure it will set up hard to the touch?