OK, this isn't directly endurance related, but I'm surprised I have only seen one posting on this that I remember. Basically, The Arabian Horse Registry of America refused to accept some horses that the World Arabian Horse Organization called pure bred. Old news. Now some of those horses are now being accepted. I spoke with AHRA and some of the horses trace to 30 Maria, a mare that was most likely thoroughbred, and to Shagya, who was not known to have left purebred offspring. A bit controversial, but not to ruffle any feathers, I've seen people point fingers at the Polish and Russian foundation stock, the French Arabs, Skowronek, Serafix and all horses w/ Muniqi ancestors.
Just something to think about if you don't already have enough gray hairs.
Shelly & Jabar & Shadow, who don't care who their ancestors are as long as they get fed