total ink stat

Does the total ink reported for a profile under “statistics” refer to the neutral axis, or builds in the entire output space?

It refers to the neutral axis. ColorThink asks for 0, 0, 0 and adds up all the numbers in order to get the lowest value on the neutral axis. But as you can well imagine, there may be incidences where there may be a more heavily inked spot outside of that neutral range.