I think Homer Simpson claimed once that music was perfected in 1969. Maybe that was due to the various drugs being somewhat new to the young musicians around that time. I used to get creative writing music with alcohol/pot back in college. Never really did the harder stuff. Maybe that can be something to look forward to in 25 years when I retire. Shrooms chased with whiskey while using the latest invention that converts your thoughts into music.
Naaa, that was just McCartney writing a children's song while completely stoned on hash. But listen to Lennon on "Tomorrow Never Knows", also on Revolver, for some serious early acid music.
CNS and sometimes Y. You don't have those extended jams without some kind of pharmaceutical interaction.