Who is she?
DGL has had all the active ingredient removed so it's basically useless.
http://drholly.typepad.com/licorice/
Sarah Ballantyne, PhD in her book "The Paleo Approach: Reverse Autoimmune Disease and Heal Your Body".
Obviously book is focused on people with autoimmune conditions which most of us probably have. I have seen places say ME and CFS are autoimmune. Also in a FB group for autoimmune paleo, they indicate if you have food allergies that is autoimmune, including any gluten sensitivity disorder.
The book is long with very many references at the end, but I don't know if any references are given regarding licorice. I have not researched further.
Thanks for that reference about DGL being ineffective. Personally I will avoid licorice in either form.