He is, and the several of the people in the peafowl forum warned him that it could severely injure the peas. We were all pleasantly surprised when he managed to tether train them without hurting them.
If it's not endorsed by Association of Avian Veterinarians, why in the world would you want to use it? If you feel the need to sedate your birds, please consult with a veterinarian.
https://www.aav.org/