Re: Because the Pegasus worked out so well for Orbital.
"However, for that, the Bearded one will have to do what NASA did with its B747 shuttle carriers - modify it into a proper launch platform."
NASA hardly modified the 747 into a "proper launch platform"; they proved that it was possible to release a light, aerodynamically modified shuttle with no fuel safely from its carrier in flight. There were some nice designs for flyback boosters early in Shuttle development programme, but they weren't 747s... I always rather liked the one that was a sandwich stack of triangular pancakes, where the outer two were boosters which peeled away and turned back to land while the middle one headed on upwards...