Originally Posted by Robert Goodman

A horse collar can only be done from behind the runner, and from there it's almost the only kind of tackle that can be done, unless you're faster than the runner and can overtake him. If you're not, about the only other way is to launch yourself at the runner's legs, which not only risks a kick in the face, but also can produce an ACL injury to the ballcarrier if you manage to get your shoulder on a leg. So it seems to me that allowing the horse collar would be safer than banning it.