It’s certainly selling a supplement - no doubt about that - but the amount it specifies differs based on the other ingredients, and it makes it easy to adjust the diet to see what works for the dog. It also appears to have been created and be managed by a group of veterinary nutritionists, so my quack-o-meter isn’t going too crazy. I’ve read through a number of topics on their moderated forum, and they’re far from hard sell: if kibble is working for the dog, they recommend the owner continue to use it rather than cooking.
I’ve read through the material on the Tufts site (Lisa Freeman is a blast from the past: she designed a diet for my RER horse ages ago. She was fantastic to work with), and it’s very good.
ETA: Speaking of Tufts resources, just came across this in thinking about how to plan my diet experiment: https://vetnutrition.tufts.edu/2017/01/food-allergies/
Tufts suggests visiting balanceit.com to design a nutritionally balanced homemade diet for healthy dogs. https://vetnutrition.tufts.edu/2018/11/sensible-use-of-supplements/ Ok, now I feel better. (Except that I was looking for thoughts on the best carb to use…)