...hasn't it settled down to that already?
A bit of damping re the comment quoting "ex military" types: I'd rather hear it from the Aussies and Italians who are currently going to war with the KC30 and KC767, respectively. Somehow I suppose they're both pretty good at what they were designed for.
Which brings us to the heart of the matter: If Boeing couldn't hit the Air Force spec with their new KC46, it's likely because the spec just didn't fit to the existing aircraft
at all. Whatever it was - flow rates, wiring standards, issues not related to the tanker mission - probably cought them unprepared; in other words, I think the whole horror is more of a project-management than a quality issue. We'll probably see in 20 years how the 46 performed in real life.