It would not be All, it will be the Out unchanged there.
So the script would have
IN (what you want the JSFX to consider), channel 1>16 or all of them
OUT (where you want to send the signal) channel1>16 or keep original.
So it is more about having an Original switch in the Out menu.
Cause having a All unchanged in Input, means that the Out value isn't relevant, and because there is no way to deactivate this via JSFX, it is a bit disturbing to have that behavior.