Thank you @lenskonig
I think the doctor was presenting evidence against the idea that LSD increases risk of suicide (even this moderate perspective was radical in the 60s). But, you're right, it should, in theory, have reduced suicides. I would guess that either LSD is not effective in the face of such immediate and profound self-abandonment, or the tool and its method of use was still in its infancy.
LSD contributed to eliminating suicidal thoughts in many people I know, including myself. It's hard to put exact figures on this until research begins again on a large scale.
The other tricky thing is that the sitter can be as important as the substance. So there could be huge variations in effectiveness that have nothing directly to do with the LSD itself.
Before a person experiences LSD it might be enjoyable to read some of the great books on this subject, like Stanislav Grof's LSD Psychotherapy.
Thank you for reading.