LMP737, that is a concern, but I think Boeing is more committed to compete than McDonnell (as opposed to Douglas) was. Airpower magazine's Jan. 2002 article on the DC-10 has this to say:
"By 1974, the Douglas old guard had either retired or moved on to different companies and the McDonnell family now dominated the company's executive committee. They mandated that no new design work would commence on any derivative airplanes until the DC-10 Program broke even.
" Although both of these designs [Twin-10 and 380-passenger DC-10 Stretch to challenge the 747] generated a fair amount of interest from prospective airline customers, various limitations in Douglas's manpower and production resources, coupled with the continuous restrictions from the St. Louis corporate headquarters, made it impossible to proceed. Regarding these strategic decisions, it was admitted by the McDonnell family in later years that they never really understood the intricacies of the commercial airplane market, and never really listened to any of the Long Beach people who did, thus the Douglas half of the company was bound to suffer."
So, I'm hopeful that the Boeing management has learned the lessons of Douglas's bitter strangulation at the hands of McDonnell.