Kodak spent a lot of money and time on research to come up with a single powder mix. Kodak has many patents on this problem. This is why Ilford's ID-11 comes in two bags but D-76 comes in just one. Each chemical may need a different approach. For example, very finely divided boric oxide is used to coat such alkalies as sodium carbonate. All the chemicals must be completely anhydrous. Even a small amount of moisture will cause the powder mix to spoil. The chemicals are also packaged under nitrogen.
When Acufine first appeared the cans started exploding on the store shelves. The developer had to be reformulated.