Interesting that this narrative is surfacing at a point when 'recreational cannabis' is about to become legal in Canada. In the late '60s I worked in a milieu that made plentiful use of 'the green herb', but when dear spouse brought me to Goa for retirement I found that (for a 'foreigner') it was a case of 'water, water everywhere nor any drop to drink'.
As of past months I begin to comprehend that any substance can be either 'used' or 'abused'; the point that 'where there are drugs there will always be violence' may be truth up to a point; but there is violence with or without 'drugs'. A Counsel that I'm promoting to the Authorities here is that 'spiritual guides' should be involved in the 'recreational use process'; the medical & juridical people have already provided proof that they cannot do it alone. My concern for the situation in Canada is that 'the money changers in the temple' are about to take over.
Bob Marley's spin on it was that King of Ethiopia was a 'reincarnation of Christ' and that Cannabis is a Sacrament. I rather think that a blessing-or-curse consequence depends on a state of mind --- if one ingests simply for the 'kicks', then kicks is what one will get; but if taken as 'God's Gift' then the heavy molecules work to kick up consciousness to a higher level.
One of the common 'effects' is 'the time-warp', with another way of 'seeing' the total equation of history-in-duration---the total amounts to more than the sum of its parts. My spiritual guru (Pierre Teilhard de Chardin) refers to the metabolic effects of many botanical and biological substances as a 'widening of the aperture'. William James in his Varieties of Religious Experience made the same point---to include alcohol.