This threshold thing is interesting. Just to make the idea itself solid, imagine this. You have a type of iron bar that can bend completely elastically (no deformation) if forces less than 100N is applied to it. Say they are more valuable if they have no such deformations. Would you apply 90N to 5 billion bars or 110N to one bar?

With this thought experiment, I reckon the idea is solidified and obvious, yes? The question that still remains, then, is whether dust specks in eyes is or is not affected by some threshold.

Though I suppose the issue could actually be dropped completely, if we now agree that the idea of threshold is real. If there is a threshold and something is below that threshold, then the utility of doing it is indeed zero, regardless of how many times you do it. If something is above the threshold, shut up (or don't) and multiply.