Not really sure what you mean, I saw people on 10mg THC wring crazy code in a crazy speed. Some of them need it to be able to focus and think clear. Drugs never work "one way" for everybody. And its not only people its many things that affect how they work (setting, culture, education etc.). And if you think man kind does not need any drugs (including alcohol), if you look at it from a historic perspective we might even need it.