The 7.3 also uses a high pressure injection system. The big difference between the 7.3 and 6.0 injectors is that the 6.0 uses "split shot" injectors which deliver the fuel in two pulses instead of one, thus running quieter. If the 6.0 injectors would be damaged by B100 then I would guess that the 7.3 injectors also would.

I wholeheartedly agree that the biodiesel is the best choice for the near future and we are wasting lots of resources that could be used to make the stuff. Like some of the others here have pointed out though, it will probably require a great deal of public dissatisfaction and action before things change.