You might remember a thread some 6 months or so ago...
Nada chance, unless you had POSTED ALL THIS IN THAT THREAD.
Pins 1 & 2 I had thought were open circuit until the key was turned...
position has NO effect on the CPP switch output; the CPP is only affected by the Clutch Pedal
So when there is no current..., you would see ground?
Yes, but ALSO when there is significantly LESS current than it takes to operate the start relay, which is ~4A. So that circuit can pass >0.4A, and the voltage won't rise significantly. It depends on how the ESOF is programmed &/or built to detect ground as to exactly how much current the circuit could pass (voltage at the ESOF pin) and still qualify as a "ground" input to the ESOF.
You're saying that the purpose of grounding the R/W is to stop the shift.
No; it's to tell the ESOF not to attempt the shift. Not to actually interfere with a shift that's already happening.
the circuit of the O/LB wire from the ESOF to the transfer case motor?
Take a closer look at the circuit: O/LB doesn't go to the motor. Then re-read what I posted before. What I'm saying is, you MIGHT be able to wire the CPP to interrupt the RANGE button, so the ESOF never even tries to make a range shift if the clutch is engaged (pedal released).
...it appears that the ESOF also solicits input from the speed sensor to determine if a shift is possible.
I don't remember ever reading anything like that, but it's been a while since I've read that TSB - I don't have ESOF, so I've never really needed to.
...being stopped in a manual transmission truck is mutually exclusive with either the clutch depressed, transmission in neutral, or engine off.
"Mutually exclusive" means any one of them excludes the possibility of any other. I think you meant something like "analagous" or "equivalent".