It's an appealing theory but unfortunately doesn't hold much water. That Wikipedia article covers the criticism. Savory himself conveniently believes HPG can't

It's an appealing theory but unfortunately doesn't hold much water. That Wikipedia article covers the criticism. Savory himself conveniently believes HPG can't be proven with science, which is a pretty big red flag. Studies suggest it is better than unmanaged grazing but not as good as no grazing. So, a useful idea but not the claimed panacea.