Have you figured out, too, why this gives different results? I can easily imagine that it would affect rounding somewhere, but if so, neither of the numbers in the abstract (172,4, 172,7, 173,2, and again 173,2) is incorrect, and the relatively large range point towards numerical instability of the algorithm.

Secondly, I would guess the reported difference between Mac OS Mavericks and Mac OS Mojave is because they tested on a Fusion Drive (I would expect the filesystem to cause the difference, and that changed with High Sierra, except for Fusion Drives, where it changed with Mojave)