Very interesting. Thanks for posting this.
Before the improvement in roads and carriages, most European riders rode easy gaited horses. Some of these natural amblers made it to colonial Canada, America, the Caribbean Islands, Central & South America. The people of the New World decided to keep on breeding amblers while in Europe they stopped breeding them in favor of TB's and dressage type horses.
Though I ride trotting horses I am really glad that the TWH is around. It is one of America's special breeds. Too bad about the shows.