One really has to dig deep into the history of each gaited breed.
It's easy to trace back the Tennessee Wakers. Rocky's and KMSHA's - not so much.
While Tobe is considered the first foundation stallion of the Rocky's, I am not aware of anything that documents who Tobe was decended from. History of the breed
If memory serves me correctly, I think I remember quite a bit of hoopla over the discovery of a small pocket of heretofore unkown gaited horses somewhere in Kentucky.
I believe that was back in the 70's and some time later the Kentucky Mountain Horse registry was founded.
Please note in the following link that credit is given to "Tobe, owned by Sam Tuttle" as the KMSHA foundation horse; that would be the same stallion that is listed on the RMH registries. Meet the Kentucky Mountain Horse - Kentucky Mountain Saddle Horse Profile
The Tennessee Walking Horse folks have kept a much more detailed account of their heritage. Breeds of Livestock - Tennessee Walking Horse
If I had to guess, I would say that the beloved Tobe, owned by Sam Tuttle, could very easily be traced to a horse with Walking Horse lineage or, the Morgan horse as Morgan are gaited whether people like it or not. There is a gaited Morgan horse registry that is trying to keep their single foot alive and well.
This link discusses all gaited breeds, in general. It clearly shows that gaited horses are nothing new in the equine world. They'e been around for quite a few centuries
Hope this helps -- at the very least reading these links will be an interesting learning experience.