The trick is, at that time most of the possible mass range was excluded experimentally, so it is a bit less impressive. I'm not sure how much tuning went into it (possibly none)

> Eichhorn and her colleagues are pursuing a different possibility. In 1976, Steven Weinberg, a theorist who would eventually earn a Nobel Prize, pointed out that if you zoomed in far enough, you might reach a place where the rules of physics would stop changing. New realms would stop appearing; the intensities of the forces would stabilize; and gravity would turn out to make perfect sense after all.