It wouldn't do to just sprinkle the weed with cocaine because you can't smoke white, crystalline cocaine. When heated, it disintegrates before it can get hot enough to vaporize. That is why you need to free-base it or cook crack from it if you want to smoke it, and the reason why crack was invented in the first place.
The entire time line makes no sense because hemp as well as coca plants of course take months and months to grow before you can harvest any product. Not to mention the decades it takes to get prohibited drugs legalized by political campaigning.