So I'm NOT the only one who's thought of this!!!
I plan on doing this on a small board I use for live play-out, to sort of organize the cable-jumble and enable exactly what
@Dennis Fieger is describing - getting a "copy" of my mix out to another destination, using the [AUX/FX SEND's].
Now, as the Village Idiot here, I'm not necessarily the one to be giving technical advice (my studio/routing skills/knowledge compared to the really smart guyz here is like asking Chris Farley for life coaching).
But yeah - I'mma pretty sure that once you plug into the [AUX/FX SEND], internal FX will be fully disabled (as the board will expect you to plug in a [RETURN] from an external FX unit. This doesn't matter to me, 'cuz all my signal sources will be fully FX-treated before they ever get to the board.
And while I haven't set it up and "test driven" it yet, I see no reason why it won't work.
Good luck - and let us know how it works for you!

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