Oh yes I've heard of it, I did an earth bag dome workshop in india in fact, but the bags used are not sustainable often barbed wire is used too and must be built properly otherwise risk of collapse, found the process to be quick hard work and of course compared to concrete its better but I do question alot of the modernised methods of building a dome structure, the idea came from the middle east but it was westernised over time and incorporated these materials that are not great for the environment.