[Balgair]

My brother used to work for an atomic clock company. Their array of clocks was the 2nd most precise next to NIST in Colorado, he said, and when small fluctuations in the earth occurred, their's was another point of contact for GPS timekeeping (allegedly). Reading through the OP, I remember that this sort of mid year leap second happened a few years back with the Japanese major earthquake. My brother said that they had to reset all the clocks about a millisecond due to the shifts in the rotation of the earth because of the quake. One would think that the programmers would have written into these market timing devices a simpler way to adjust these calculations, seeing as these timing updates keep on happening.