By the way, the article notes that all the teeth were grinders but the creatures pelvis showed only slight widening. How long you figure it takes to transition to all grinders and how much larger must the creatures gut expand to suck the nutrients out of foliage to survive at that size? This sounds all backwards to me. Predator to prey. All choppers to all grinders with little change in gut capacity. Carnivore to herbivore.
If you told me the creature had a mixture of grinders and choppers I'd be more inclined to think that it was transitioning from something to something because I could understand an advantage. As is, I don't see it. But then again, neither did anybody else.