I don’t really know the methodology, there was a link to it on one of these threads. I suppose if you were designing such a study, you could start with people who don’t use it, and have them do something that requires physical and mental coordination. Then you give them x amount of THC and test them again. Presumably they would be impaired. Then repeat that over time and see if they perform better on he drug as time goes on.
My guess is that ‘road rage’ is dimished with those who are high...they can just wave it off and chill out until the light changes....lol Speeding has slowed as they really are trying not to mess up....oy vey....just speculating here.