By the way, I did notice that Half & Half removed deer-tongue from their blend several years ago. The absence of the "green deer-tongue-leaf" is noticeable in smoking and visual perception. The reason it was removed? Expense and very hard to come by in modern blending.
The herb, deer-tongue, is not toxic. It is essentially a vanilla "type" flavor but tilted in a different direction. Vanilla by itself is "flat" unless enhanced with another spice or flavoring ingredient. When appropriately enhanced, vanilla extract gives a companion flavoring an extremely smooth and mellow characteristic.
Deer-tongue is extremely expensive and hard to come by. I remember the "late" Craig Tarler of C&D telling me that he acquired a pallet of deer-tongue (quite expensive) and that he was guarding it with his life. If you try a blend containing deer-tongue, please use a specific pipe for it. You can never get rid of the "ghosting" of deer-tongue. I have two pipes dedicated to such blends and nothing else. I am rewarded for that when I smoke a blend containing deer-tongue. It's worth trying. Just don't use a pipe that you may desire to convert to a non-deer-tongue blend as you will "always" taste the herb. I also enjoy Gentleman Caller from time to time in a specific pipe dedicate only to that blend due to "ghosting".
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