The original idea of the 'stone'(don't have a clue as to why it was named that other than consistency) was to make mixing easier and more consistent for those wanting to be accurate in repeating their diy mixes. They did not have benefits of readily available equipment to use or many recipes in which to choose from, most calculations used long hand, etc. So if they found combinations that they liked they wanted to be able to keep doing it easily, accurately and quickly whether it was for single-mixed flavor combinations or a whole recipe. Well you get the picture.
Today is a whole different environment where for anyone who wants to mix, its a relatively straight forward process. To separate the different functions that originally comprised the name of stone, it makes sense to separate and rename 1 of them. At least this is how I am seeing it. I could be wrong also. So I always say, if it fits wear it. If it makes no sense throw it away.