I have done this taste test with most of them. I read about
it in the Buhner conference notes under How to Tell Which Herbs Are Right for You -
www.betterhealthguy.com/buhner-conference-notes.
I could tell there were a few I responded very positively to. Lion's Mane was one. I haven't taken that in a long time. I do the test again every now and then and find that my responses change over time and are not always reproducible. I do think it's a good, though subjective, way to gauge your response to different herbs.
Even those I responded negatively to I kept taking if they were in the bartonella protocol, as I felt it was important for me to do as much as I could. I found in most cases that those were the herbs I had a hard time increasing doses on.
I do not personally think taking only herbs I respond to in a noticeably positive way is a good policy. To me, it would be kind of like eating only foods that bring you pleasure rather than what you need. Hope that makes sense.