I thought that 15% seemed to be a really low amount, so I calculated the approximate percentage of my weight. I way about 116 pounds (on a good day) so we'll say I weigh 120. My mare weighs approx. 1200 pounds. That means that I'm 10% of my horse's weight. 15% percent of her body weight is 180 pounds. I honestly don't think 180 is that bad! Now if it were a smaller horse, like my gelding, who only weighs about 1050. I'm 11, almost 12 percent of his weight. For a horse that ways 1500 pounds, 15% is only 225. It is just me, or does this not sound a bit ridiculous?