By way of the the Secular Buddhist Association, a couple of videos featuring James Fadiman and Kokyo Henkel discussing the crossover between Buddhism and psychedelics.
Buddhism and Psychedelics part 1
Buddhism and Psychedelics part 2
I enjoyed part 2 which had more Q&A. My take is that there is definitely something there, particularly the idea of getting a quick helicopter ride to the top of the mountain.
Additionally, the psychedelics help point out the jhanas. The classic first "big" spiritual experience of bliss, love, and light points pretty clearly to 2nd jhana. And you ain't experienced 5th jhana (infinite space) until you've experienced it on psychedelics (or spent years cultivating it). That sucker is big.
And, I think small or microdose amounts can be judiciously used to gauge progress. Over time you see more and more subtle things opening up.