@ej2eugene Don't you think that the FX loop working on both channels is somehow useless? I mean the way it work it can be made by plugging effects pedals after the F1. not only that but you then have to use less cables (using pedal in FX loop=need 2 cables, using pedal after the F1=need only 1 additional cable)
The only use I see is having several preamps and using one particular set of effects (eg. the F1 with chorus and reverb, then the mesa boogie preamp with delay...)