This is liable to put the drug testing companies out of business, which is one reason why i think the feds will keep it illegal for a long time. Reasoning be, cannabis stays in your system for a long time, while the other drugs that are actually ruining peoples lives, and even killing, stays in your system for only 3 days. So if cannabis was allowed, these tests would be almost obsolete, being any person on dope can stick the 3 days out to pass a drug test.