Yeah, the breeder reactions are good because they can burn long lasting isotopes, generating short half life and more easily disposable materials, but they also

Yeah, the breeder reactions are good because they can burn long lasting isotopes, generating short half life and more easily disposable materials, but they also make more of the risky isotopes (those with low critical mass that are more easily/chemically separable). Thorium is quite a bit better about that (not perfect), but it's even less well understood for actual reactor design and production.