Well, Anthropic used model A to output the version 1, and then used model B to rewrite the version 1 into version 2, so the handoff was machine to machine and not human to machine. I read that part of an article as if it was their internal assessment test of their new model B (Fable) capabilities so that they can see if the new model can find interesting things but by intentionally being vague and without implementing the bias into your prompt. I use this technique very often as well for two major reasons: (1) I don't know what I might be missing so I let the model do the unbiased exploration of problem space, (2) I am curious how far the given model has come with its capabilities. What Antrophic did in this case is an example of (1) and I wouldn't really call it creative since anyone could prompt the model with "rewrite this code".