In shamanism and certain yogas, Taoist yoga, claim very clearly that the purpose is to familiarize yourself with this after-death body, in life, and then the act of dying will not create confusion in the psyche. You will recognize what is happening. You will know what to do. And you will make the clean break.
The psychedelic experience is the beginning of the spiritual path. That's why it's not important that yogas' claim that they can deliver you the psychedelic experience, because it begins with the psychedelic experience, and then you go from there.
Patanjali specifically says that there are three paths to the goal of yoga. And they are, control of the breath, control of posture, and light-filled herbs. It says it right there. Stanza 6 of the Yoga Sutras of Patanjali.
