The idea at Focus is to take young kids who barely have a CFI and throw them in the FE seat for a couple of years paying next to nothing and then upgrade them to the right seat. The difference between an SO and a PFE is an A&P license that PFE's have and SO's do not have and that the SO is sooner or later going to transition to the right seat. They have I believe 12 "cadets" at Focus for this type of training. But they are having a real problem with the FAA because the Fed's don't believe the 747 is a good platform to start an aviation carreer on.
I agree with the Fed's however I know in Japan they have been training pilots from CFI with 250 hours to right seat 747 for over 20 years. But in Japan they always used PFE's. And training is much more intense.
Major carriers have used the "SO" for years on three men acft.