yesterday I was taking a short gallop up a hill and sure enough, there's a walker coming in from the shadows of a trail adjoining from the right. Z spooked left, and I had a momentary "oh oh, I hope I don't go off".
Well, I didn't, and I stopped to recover myself and talk to this person, who was also surprised. In hindsight, I should have asked him right back up into a canter, even if for just a step or two, so that spooking is not associated with an entire stop of acitivity.
I didn't pat him, I didnt punish him or yell or make any big deal, which is good, but the next better thing is to carry on totally.
It's important not to reef on your horse's mouth or punish them if they have a genuine spook. If you can, go with them for a step or two, then channel that energy back into work. That's what we SHOULD do, but what I often do is just be thankful I am still on, and recover my dignity , then think about moving on.