I wonder about conformation too. For instance. My Fox, he is so huge when he spooks he cant really spin. But he can rear. My stonewall can whirl front to back in a split second. He has never reared. My Jaspar when young would jump sideways right out from under you. But I have been on him on rides where a "flight" ocurred. a "flight" is when something happens and they all bolt. a natural herd thing. When a deer leaps out of the bushes into a long line of horses on the trail etc. That happened to me two or three times, and all the horses bolted in a "flight". Some ran two miles. Some took off crashing through the trees knocking riders off, jaspar is so lazy and basically slow that he only bolted about fifty yards.
So any horse will bolt. But conformation has a lot to do with it I think. Parelli says when you force a horse into a corner he will show you what he has left in his bag of tricks. Janice -- yipie tie yie yo