Earlier, "Bill Daniels" wrote:

...Nope, it needs 600 Kg to allow for
three 'super sized' customers.

I believe that trying to accommodate the maximum doesn't make good
economic sense. I still think that the way to maximize the economic
return is to optimize the vehicle for a cockpit weight that falls near
the middle of the bell curve for groups of four. And I'll bet that's
no where near 600 kg.

Bob K.