> Together, these trees produce 40 new branch heads and 400 new commits on an average working day. Each day,
This sounds low to me. Based on the 176 changes/day that the mainstream has, I would have expected that covering mainstream, linux-next, and the trees that feed into these would result in a much higher combined totoal.
However, it's impressive that a farm of only 13 systems is able to do this sort of testing on even about half this rate.