Great remind about unsuccessful ideas; as I prefaced my original remark, I am impressed by his accomplishments. And I have no doubt that he (or someone else, eventually) would be able to build engineered organisms that could "work" (in the small sense), and survive and reproduce (and so work, in the larger sense). But that success is pretty distant from being able to predict and control the long-term effects once they're released. [edit: spelling/undo autocorrect]