Kevin, I agree with your comment about paying attention to the horse
when it alerts. Many times the horse can hear or smell things long
before I ever do. I swear my mount can hear people breathing, if they
are within 75 yards from us. I am a Member of TROTSAR in Maryland and
our newer team members are told about this topic while they are in
training. But like you said, not all horses pay attention to those things.