Your horse sounds perfectly fine. I've had my fair share of good horses as well. But I have also been alive for three hundred years and have seen more than my fair share of horses bolt and cause serious injury-to-death for no more than seeing some small movement out of the corner of their eye, or otherwise a deer or other animal startled them. I'll give you the being startled by cannon fire.

[Everyone is, that's normal.]

--They're certainly different. Horses don't require me to sit and think through every step of operation.

[he doesn't know and doesn't care to learn]