Yes, in addition to what others have said here, depending on the horse’s personality (horseonality?) some go completely bonkers when kept on “stable rest,” such as you’d need to do with a sling. And by bonkers I mean throwing themselves at walls, biting themselves, and gnawing just about anything to try to escape. They’re likely to hurt themselves worse before being able to heal, and even if they do heal (I have a friend who did this against the vet’s advice), they may have become so neurotic that you can never ride them again.

I couldn’t agree more. I read them quite some time ago, and still find myself having philosophical discussions about them somewhat often today. Most are really thought provoking in a non-judgmental way.