Jeff,
I recently heard some persuasive discussion Doug Lisle was a part of, regarding placebo effect not actually performing as many of us have long understood it to, especially concerning long-term. Is this your understanding as well?
For example, it does more of what I would have expected before my statistics class taught me otherwise: it likely doesn't have any drug-like effects, but rather more just hope or at least perhaps inaccurate self-perception of or reporting of feelings short-term, and no effect long term. Somewhat like was found in this study: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4303345/
In other words, compared to no treatment at all, a placebo should in reality have no actual effect other than some hope and what a subject might get into their own head and report despite there being no real difference other that what they are now looking for and over-reporting.
Audio of the discussion:
https://www.youtube.com/watch?v=EEpHB1bzmXQ&t=0h01m58s
Approximate transcript of the discussion:
http://stephawkes.com/doug/123.html#45