The conclusion of this study is presented trickily. Of course, adolescents shouldn't smoke pot, drink alcohol and a multitude of things. Their brains are still developing. Like alcohol - pot should be used only by adults, and then - only responsibly.
You wouldn't drink and drive - you shouldn't toke and drive. DUH!
As addictive as heroin? How about as addictive as chocolate? Addictive personalities are going to get addicted to something! It's their nature.
Schizophrenic people are going to try anything that might help stop the voices. They will be drawn, first to pot - and then their dealers will get them to try harder, more addictive and profitable drugs. This is a consequence of pot being sold by organized crime.
This study is hogwash. I wonder who paid for it - probably a pharmaceutical company. Wouldn't want people to be able to grow an herb in their own yard - bypassing big Pharma - now would we?