So, like...I could see bravery playing a larger part for lower leveled horses (less training/experience) than it would a horse with more training. Of course, I'm just talking shows since I can't really see how bravery would affect a horse's breeding potential.
I've had the same experience with my show horses. I had one mare who would spook at her own eyes blinking and then be perfectly fine with having a gun shot off of her or fireworks going off as long as someone was on her back
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