the magnitude of effects of such work is large enough that “positive sign” often is enough information to decide that it dominates many alternatives, though certainly not all of them
FWIW, my guess is that this is technically true if you mean something broad by “many alternatives”, but if you mean something like “the best several alternatives that you would think of if you spent a few days thinking about it and talking to people” then I would disagree.
FWIW, my guess is that this is technically true if you mean something broad by “many alternatives”, but if you mean something like “the best several alternatives that you would think of if you spent a few days thinking about it and talking to people” then I would disagree.