[myrmidon]

I'm unsure what exactly you mean by sigmoid stacking.

I'd argue that a lot of important technologies (like circuit design!) started at basically zero in the last century, and the progress was actually exponential for a significant time (=> because we started so low on the curve).

But if you reduce things to a single metric (wealth per person? total energy available to humanity? global industrial/construction output in tons?) I can't think of anything where such "stacking" successful subverted the sigmoid trend (or looks like it will, long-term).