We would always make sure to have plenty of supplies. Art or otherwise. Pen and paper was probably the most difficult. The effects on your vision are pronounced and drawing can be... hard. I always enjoyed oil pastels the most. Thick and flowing pools of color. Man those were good times.
I was in art school at the time, and critique (the ability to give and receive) was one of the greatest things I walked away with. We would formerly critique on a regular basis in class.
> I don't doubt they had a good time, but seeing them utterly fail to use the drug as a tool kinda makes me skeptical of the productive benefits.
This is akin to coming onto a software project, seeing a huge tangle of grotesque code produced by some other programmer(s), and determining that the tools were at fault. In both cases it is not necessarily the wand, but perhaps the magician.