A reasonable reaction would be 'tell me about the difference it makes to your symptomology' and maybe helping the patient figure out a way to track this systematically. Likewise I would have thought that mentioning my extensive experience of psychedelic drugs (also now suddenly fashionable) would have merited something other than 'uhuh', such as questions about how the temporary improvement in mood manifested or how long it lasted. I manage to have very interesting conversations on subjects I know nothing about by the simple method of asking people questions about the domain knowledge they've acquired, and I doubt that any psychiatrist has ever lost their license for listening too closely to their patients.