I read on reddit that hemp was banned by the lobbyists of the lumber/timber corporations, as hemp was dirt cheap to grow and process it to make paper, which of course would have killed these big paper corps. Marijuana being a cousin and seemingly looking alike was banned together with it. any truth in this?

Ok. marijuana affecting hacking abilities (in terms of driving) video link: http://www.youtube.com/watch?v=t3zou4F00Ic (i think this is from channel-4 UK)

In there he says he is "concentrating more and driving slower".