Most people completely shave/trim their horse's facial hair. Bridle path, whiskers, throatlatch, jawline, etc. I've always thought the whiskers serve some purpose (although probably not as much as a cat's) but its frowned upon to not clip in bigger shows. How do you feel?

That like you say they serve a purpose. Just like the tail is used to swat flies and keep the horse comfortable I think that that facial hairs serve a purpose. You're horse might not walk into things because of them being gone but it will have some affect.

I really don't know. I mean, there are more than one body part on different animals that don't serve much purpose, think appendix in humans, and the curly tail in a pig. Maybe the whiskers were at one point useful but are no longer. Or maybe they are still. They could detect air particles like a snake or something like that. I would rather just leave them, just in case.

Sure the appendix isn't needed but the comparison seems a little redundant. The issue is more like cat's whiskers, which we know are useful to them.

A pig's tail does serve a purpose, it covers the anus and girl-bits (if it is a girl) so that they're protected from wind, sun, hail etc. They get cut off in factory farms because bored pigs tend to chew each other.

I think the horse can manage without its whiskers, but I think they do have a purpose. A horse has a great big nose, do you think it can see things directly in front of its mouth? It might need those whiskers to feel what it cant see.

That's a very good point-the shape and size of the horse's nose could make it very hard to see around. The whiskers would be a good warning system that they were about to bosh the nose on something.

I've always hated some of the things you have to do to show in the bigger circles. You almost feel like a sell-out to keep up and compete. Shaving Trigger isn't any different than wearing tons of makeup (after all you need stage makeup to be seen from the judges seats) or buying flashy outfits or using polish on the hooves.

So long as you don't move your horse from his/her usual stall where they would need to know where things are they should be fine while they grow back. Although with so many full-time show horses they must deal without them. I've never read about a show horse losing his head without whiskers, you know?