Lots of good theories in here.
There was a point I was smoking a QP a week, but that has been quite some time now. My brain does not function any more, so I had to quit. I think that dehydration plays a large roll in the hang over/lack of motivation. I notice now that when I am dehydrated that I feel demotivated as well. I don't smoke any more either. If you read marijana Growers Guide by Ed Rosenthal he has a good explaination in there about the chemical makeup of pot. CBN, CBD, THC etc. THC being a psychoactive substance turns into CBD with exposure to air. The CBD is what makes you drag ass. THC makes you happy and laugh, euphoric. Definately can confuse you as well though as far as I am concerned. Definately not the stuff to be smokeing when you are trying to program. Maybe when you are doing some graphics up, that is one thing.