I think it can. But I don't know if it is predictable enough to put to good use. A few years ago, I was really loaded on both speed and weed. My brain was going crazy, and I thought "I have to write some of this stuff down". Well, it turns out that I thought I had discovered a cure to cancer, and some other of lifes big mysteries, and I did write it all down. When I read it after I was sober, I realized that drug really can put you into a hyper-creative state of mind. No, I don't think I cured cancer, but the stuff was really interesting(to me anyhow).
I still have those papers somewhere, and if I can dig them up, maybe I'll scan them so you can all see what drugs can do to a brain.
I know this is a different type of creativity, but drugs definitely put my mind in a place that isn't normally accessible to me. There is no reason why it couldn't do the same for any artist.
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Those who speak, don't know.
Those who know, don't speak.