One factor that will be difficult to evaluate is how predictions have interacted with later events. Warnings can (at times) be heeded and risks avoided. Those most difficult cases might be precisely the ones of greatest interest given your aims of shifting humanity's odds.

A related question is how much impact these predictions had (aside from their accuracy). Things like Limits to Growth or The Population Bomb were extremely influential in spite of their predictive failures (once again, leaving the hypothesis that they served as self-refuting prophecies).

Once you have a better sense of these cases, it will also be interesting to evaluate how responses developed. Were the authors or predictors influential in the resulting actions? You mention at least one case in the email thread where the author was shut out of later efforts due to the prediction (Drexler). I'd be curious to see how the triggers interacted with the resulting movements or responses (if any).