Do the nails in the horses hoof hurt?
If you have ever been behind the scenes anywhere they have horses( such as in a barn) and you happen to witness the changing of horse shoes, it looks like an extremely painful process. First the nails must be removed from the old shoe, and then a new shoe must be nailed in.
When you watch the horse, they display no discomfort during this process, so no, it is not painful in the least.