I took feeding classes at Cal Poly and at special classes from the Keenland Vet of that time for professional level race and show horses. One of the groups of veterinarians we had for decades said Bermuda grass is the perfect feed, but horse owners do not like the grass tummy it often gives a horse. AND as noted in the article, as a horse outlives the old life expectancy of horses in the wild, or working on farms, (I had many horses in their thirties, and one who was forty, two friends had horses and a pony that lived into their forties) their teeth and tummy might have a harder time with stem hay. I think THE most important advice is to spend the money to have your vet, who knows your horse, take the necessary tests, and find the perfect feed for your horse, as the activity level changes, and as age comes along. I fed moistened cubes with pellets and shaved carrots to my forty year old horse, he also got three types of hay and Bermuda grass. He might chew chew chew on one bite of grass, but enjoyed it, and knew enough not to swallow big cuds, or he would choke. Other older horses, I had to cut up the hay, or they would choke, so more moistened cubes, and pellets with shaved carrots. Moistened cubes, I used HOT HOT water just enough to sit ten minutes and be absorbed with supplements, and some molasses thrown in (A little, not a lot) gave my old horses a chance to chew, but not choke. Some people like beet pulp, I always sprinkled it like salt or other seasoning, in the cubes before moistening them. Beet pulp can easily cause choke, especially in an old horse. It does help keep the intestine hydrated, but also can build blocks and colic up your horse. SO ask your own vet. I have many friends who feed only pellets, but I find they also have a lot more colic. At the track and all of the professional barns where I worked, the horses ate vet assisted combinations of pellets, supplements, etc, and it was ALWAYS moistened with HOT HOT HOT water and let cool which was just the right way to not cause choke. AND they had three to five different kinds of hay in little hay bags twenty four hours a day, only removed two hours before a race, or performance. I stick by the vet advice and testing, I have seen many horses over the decades who have allergies, or unique tooth, or tummy problems or even thyroid disease or other real medical conditions that mean certain feeds can not be fed.