The 767-KC46 was done almosat entirely by newbies ( the pointy end wIth widows is the front- really ! ) with a large dose of 787 mis-management and a plethora of MDC ex- spurts.
For whatever it's worth, there were lots of "MDC ex-spurts" early in the P-8 program. Indeed, early on, the MMA program (Multimission Maritime Aircraft), the precursor to the P-8 program, was run out of the Douglas facility in Long Beach. It was not until Boeing had won the proposal against Lockheed that the program moved north, taking with it more than a few Douglas folks. And some of those folks were the folks that developed the moving aircraft assembly line on the 717 program in Long Beach and applied it to the 737 production line in Renton, where it's still in use (albeit in a much further refined state.) And it was the MD-95 program (which was renamed 717 post merger) that first developed the current standard business model of giving suppliers more design authority and with it risk sharing.
And about that tanker program: the
early tanker program was run out of Long Beach as well, using engineers that developed the KC-10 and its Advanced Refueling Boom, along with the RARO (Remote Aerial Refueling Operator) station developed for the Dutch KDC-10. But they got pushed aside by the KC-767 folks in Seattle who basically came up with a wide body KC-135, right down to the old limited envelope KC-135 refueling boom. It was not until AFTER winning the protest that Boeing put the KC-10s FBW advanced refueling boom and an advanced RARO station on the KC-46.
My guess is that Boeing will be able to drive cost out of the KC-46
during full rate production the way they drove cost out of the P-8. Indeed they'll have to if they hope to ever recoup the billions in company money they have sunk into the KC-46 program.