Yes, it is a method for desensitization. The term came from using a sack (burlap I think) to rub all over the horse.
I start with one thing, like a feed sack (not the paper ones), and transition through all kinds of things. One of my favorites is a yellow slicker. It's amazing how many horses I've come across that were scared of them, and in our trail classes, we often have to pick one up and carry it. :) Posted via Mobile Device
I don't find that people ride on busy roads like we had to in the UK to get anywhere so maybe the horses don't see so much of life.
How is lovely Shropshire? I lived there once and was so sad to leave. My son was born there.