Hi Tobi! and I would agree with your mother on both points..and have found rosemary to go with all hair colours- being a great all rounder in that regard..with Chamomile's use to make hair lighter supposedly going all the way back to the Romans...
I guess I was hoping that someone might have some suggestions or ideas as to why the shampoos were having quite different effects on finer western type hair and the thicker Korean hair, as I have never had this happen before...