I was always under the impression that pot was 'benign' until a few years ago when I had a horrible experience with it.
I do not use any type of substance (inc alcohol) in terms of drug use for 'fun' since college (years ago) but there was this bachelorette party....
To make a long story short, my friend cultivates pot (complete with the hydroponic lights, nutrients etc) and she made pot brownies.
She showed me once how she did it.. she extracts as much THC from the pot by 'cooking' it, mixes that with butter and adds to the brownie baking process.
So back to this party... I took a small corner off of ONE brownie. A fraction of it and ate it. I went from giggling to sheer panic attacks, hallucinating and palpitations.
I wanted to go to emergency but my friends told me to ride it out. It was the most terrifying experience I have had on any substance. It messed me up for weeks actually.
My doctor (psych) at the time explained to me what had happened, that I was one of those who have negative reactions from pot and because she had extracted so much THC, she condensed it to be way more potent than smoking.
Long and short of it, if my friends were not there, I could have run into the street, couldn't have driven or if I did, would have had a horrible accident. I was so wacked out, short of breath and spent the rest of the night in panic as my friends made sure I was at least safe.
I no longer think it is benign. A cautionary tale I guess you can say.
This is a personal story. It can really be a miserable experience and cause hallucinations if used so potently.
I will never touch the stuff and making something legal also doesn't make it benign (as we know from alcohol which is legal in most places).
Sorry to ramble. It is just an interesting topic that has many sides.