Shetlands with hackney bloodlines were allowed only because a long time ago, people were passing non-shetlands off as shetlands. The registry opened itself to ponies that were part-hackney for a time (registered as "B"or modern shetlands and in some ways like Appendix QHs) I assume this was to level the playing field for all breeders in the modern division. If Lewella is on, she could tell you much more about the history, but I don't want to hijack this thread with it. ASPC later closed its books. IMO, they should have initially handled these like Arabians or other pedigree-based breeds do and registered them as "half-breds", not as full shetlands. But that is water under the bridge now and a whole different discussion. But you "hardship" into a height or maybe a color registry, not to a breed registry, and the current rules do not allow registry if you can't proove ASPC parantage. That is what I was referring to. If a horse can proove ASPC/shetland parentage, I personally would have no problem with it.