Anyone tried one of these on their Duramax?

[WhatExit?]

I didn't say it did any TPS translation. It is just a commanding a throttle position via the pedal. You could turn the pedal into an on/off switch if you wanted to with the PC (in theory).

What I'm saying is that the throttle blade has a finite limit of speed to open. You can command it to move further or quicker up to that "top speed" with a slower pedal movement with less travel. - that is all the PC does, and that is all I'm saying. It will take out lag and softness of the throttle in casual driving. In casual driving you are not moving your foot faster than the throttle blade can go. Or you can just command more throttle with your right foot more aggressively.

If you are racing for instance and using heavy and quick throttle inputs via your foot, it won't do much of anything. In fact you will have less throttle control on the upper half of the pedal travel, because you have modified the throttle curve.

I will agree that some DBW systems really suck and the PC helps with feel, but it is not doing any magic being plugged inline to the throttle pedal, it is just modifying the signal, but not beyond the mechanical limits of the throttle body.

Lots of words that don't address the issue...

It's simple: Giving a vehicle more "gas" doesn't make it respond faster
This is about THROTTLE RESPONSE not power