As of today, I have 6 Chilhuacle Negro sprouted. My take on its flavor is that it may resemble that of Basque pepper (pima d'Espelete), also an ancient landrace, though originating in Peru. If the last two germinate, then I may also try growing the Chilhuacle Negro in a pot as well, though it sounds like the roots may go down more than 12".
On the subject of exploring peppers, one year I grew golden California Wonder bell peppers, dried them at the yellow stage, ground them, then waited. After several years sitting in a jar, it gradually turned a deep, red-brown, looking just like common chili powder. While still quite mild, it now imparts a rich, chili flavor to foods, without the heat. All very strange.
Bob